Phosphonates with reduced toxicity for treatment of viral infections

ABSTRACT

There are provided, inter alia, acyclic nucleoside phosphonate compounds having reduced toxicity and enhanced antiviral activity, and pharmaceutically accepted salts and solvates thereof. There are also provided methods of using the disclosed compounds for inhibiting viral RNA-dependent RNA polymerase, inhibiting viral reverse transcriptase, inhibiting replication of virus, including hepatitis C virus or a human retrovirus, and treating a subject infected with a virus, including hepatitis C virus or a human retrovirus.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/499,865, filed Sep. 29, 2014, which is a continuation of U.S.application Ser. No. 13/649,671, filed Oct. 11, 2012, now issued as U.S.Pat. No. 8,846,643, which in turn is a continuation ofPCT/US2011/032558, filed Apr. 14, 2011, which claims the benefit of U.S.Provisional Application No. 61/324,224, filed Apr. 14, 2010, each ofwhich is incorporated herein in its entirety and for all purposes.

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH OR DEVELOPMENT

This invention was made with government support under grant numbersAI-071803, AI-076558 and AI-074057 awarded by the National Institutes ofHealth. The Government has certain rights in the invention.

BACKGROUND OF THE INVENTION

The hepatitis C virus (HCV) is the leading cause of chronic liverdisease worldwide, infecting an estimated 170 million persons. Antiviralresearch directed toward the development of improved treatment methodsfor chronic HCV infections has focused mainly on inhibitors of the NS5Bpolymerase. See e.g., Brown, N. A., 2009, Expert Opin. Investig. Drugs18:709-725. Indeed, treatment of hepatitis C virus (HCV) infectionremains an important unmet medical need due to the inadequacies ofcurrent interferon-based therapy. See e.g., Falck-Ytter, Y., et al.,2003, Ann. Intern. Med., 136:288-292. In the United States there are 3to 4 million persons with chronic HCV infection. See e.g., Armstrong, G.L., et al., 2006, Ann. Intern. Med., 144:705-714. A number of agents arecurrently in clinical development for HCV including NS3 proteaseinhibitors and NS5B antiviral nucleosides and non-nucleoside polymeraseinhibitors. See e.g., Sarrazin, C. & Zeuzem, S., 2010, Gastroenterology,138:447-462. Clinical and in vitro data indicate that resistancedevelops readily with protease and non-nucleoside polymerase inhibitors.See e.g., Sarrazin, C, et al., 2007, Gastroenterology, 132:1767-1777;McCown, M. F., et al., 2009, Antimicrob. Agents Chemother.,53:2129-2132; Howe, A. Y. M, et al., 2008, Antimicrob. AgentsChemother., 52:3327-3338. Nucleoside inhibitors which target thecatalytic site of the NS5B RNA dependent RNA polymerase have been shownto be active across different HCV genotypes. See e.g., McCown M. F., etal., 2008, Antimicrob. Agents Chemother., 52:1604-1612.

A current therapy for chronic hepatitis C includes combination treatmentwith weekly injections of pegylated alpha-IFN (pegIFN) and daily oralribavirin (RBV) administration. PegIFN/RBV treatment is effectivein >75% of patients infected with HCV genotype-2 (HCV-2) and genotype-3(HCV-3), but most patients in North America, Europe and Japan areinfected with HCV genotype-1 (HCV-1) and only about 40-50% of HCV-1patients respond to therapy with pegIFN/RBV.

There are currently only a few anti-HCV nucleosides in clinical studies.See Table A.

TABLE A Selected HCV polymerase and protease inhibitors in developmenttaken from (Brown, N. A., Expert Opin. Investig. Drugs 18: 709-725(2009)). Development Compound Sponsor phase Comment Nucleoside HCV NS5BPolymerase Inhibitors (NIs) NM283 Idenix-Novartis IIb Development(valopicitabine) discontinued 2007 R1626 Roche IIa Prodrug of R1479;development discontinued 2008 R7128 Pharmasset-Roche IIa Prodrug ofPSI-6130 IDX184 Idenix Ib Phase Ia data in healthy volunteers MK-0608Merck Late preclinical PSI-7851 Pharmasset Ia Preclinical data ≧3 othersVarious sponsors Preclinical No data available

Some acyclic nucleoside phosphonates (ANPs) are antiviral agents withactivity against double stranded DNA (dsDNA) viruses, or viruses whichrely on reverse transcription such as HBV and HIV-1. See e.g., HostetlerK. Y., 2009, Antiviral Res., 82:A84-98; Money, J. D. 2009, Antimicrob.Agents Chemother., 53:2865-2870; Hostetler, K. Y., et al., 2006,Antimicrob. Agents Chemother., 50:2857-2859. We previously reported thatoctadecyloxyethyl 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine(ODE-(S)-HPMPA, 1) exhibited antiviral activity against genotype 1b and2a HCV replicons. See e.g., Wyles, D. L., et al., 2009, Antimicrob.Agents Chemother., 53:2660-2662. Some acyclic nucleoside phosphonates ofthis class (i.e., HPMP series) are broad spectrum anti-DNA virus agents.See e.g., De Clercq, E., 2007, Biochem. Pharmacol. 73:911-922. Somecompounds of this class have been reported to be inactive against RNAviruses, including HCV. See e.g., Holy, A., 2006, Antiviral Res.71:248-253. ODE-(S)-HPMPA has shown cytotoxicity. See e.g., Wyles etal., 2009, Id.; Beadle, J. R., et al., 2006, 1 Med. Chem., 49:2010-2015.

Koh et al. prepared 2′-C-methyl phosphonate analogs of adenosine (Koh,Y., et al., 2005, J. Med. Chem. 48:2867). Others have reportedphosphonates with weak anti-HCV activity. See e.g., Mackman, “Synthesisand antiviral activity of 4′-modified carbocyclic nucleosidephosphonates (CNPs),” Collection Symposium Series 10:191 (2008); Sheng,X. C. et al., 2009, Bioorg. Med. Chem. Lett. 19:3453-3457.

There is a need for improved anti-HCV therapeutic agents, i.e. drugshaving improved antiviral and pharmacokinetic properties with enhancedactivity against development of HCV resistance, improved oralbioavailability, greater efficacy and fewer undesirable side effects.The present invention provides solutions for these and other needs inthe art. For example, we have found, inter alia, that derivatives ofODE-(S)-HPMPA modified by alkylation of the acyclic side chain hydroxylare surprisingly potent inhibitors of HCV replication in vitro andimportantly are much less toxic than ODE-(S)-HPMPA both in vitro and invivo in mice.

BRIEF SUMMARY OF THE INVENTION

There are provided, inter alia, phosphonate ester compounds havingbiological activity, e.g., antiviral activity. There are also provided,inter alia, compounds having inhibitory activity for viruses, e.g.,inhibition of hepatitis C virus replication. In some embodiments, thecompounds are substantially less toxic than previously known antiviralphosphonates, e.g., anti-HCV phosphonates, while retaining excellentantiviral inhibitory activity, e.g., inhibition of HCV. There are alsoprovided, inter alia, improved anti-HCV therapeutic agents.

In a first aspect, there is provided a compound having the structure ofFormula (I), or pharmaceutically accepted salt or solvate thereof:

With reference to Formula (I), B^(N) is a substituted or unsubstitutednucleobase. L¹ is a bond or —O—. R¹ is halogen, —CF₃, substituted orunsubstituted alkyl, substituted or unsubstituted cycloalkyl, orsubstituted or unsubstituted aryl. In some embodiments, if L¹ is a bond,then R¹ is halogen. In certain embodiments, if L¹ is —O—, then R¹ is—CF₃, substituted or unsubstituted alkyl, substituted or unsubstitutedcycloalkyl, or substituted or unsubstituted aryl. R² is a permeabilityenhancing moiety, a phosphate, or a diphosphate.

In another aspect, there is provided a pharmaceutical composition whichincludes a compound of Formula (I) and a pharmaceutically acceptableexcipient.

In another aspect, there is provided a method of inhibiting a viralRNA-dependent RNA polymerase. The method includes contacting a cellwhich includes a viral RNA-dependent RNA polymerase with an effectiveamount of a compound of Formula (I) thereby inhibiting the viralRNA-dependent RNA polymerase.

In another aspect, there is provided a method of inhibiting a viralRNA-dependent RNA polymerase. The method includes contacting a viralRNA-dependent RNA polymerase with an effective amount of a compound ofFormula (I) thereby inhibiting the viral RNA-dependent RNA polymerase.

In another aspect, there is provided a method of inhibiting a viralreverse transcriptase. The method includes contacting a cell comprisinga viral reverse transcriptase with an effective amount of a compound ofFormula (I) thereby inhibiting the viral RNA-dependent RNA polymerase.

In another aspect, there is provided a method of inhibiting a viralreverse transcriptase. The method includes contacting a viral reversetranscriptase with an effective amount of a compound of Formula (I)thereby inhibiting the viral RNA-dependent RNA polymerase.

In another aspect, there is provided a method of inhibiting replicationof an RNA virus (e.g. a hepatitis C virus or a human retrovirus). Themethod includes contacting a compound of Formula (I) with a cellinfected with an RNA virus thereby inhibiting replication of the RNAvirus.

In another aspect, there is provided a method of treating a subjectinfected with an RNA virus (e.g. a hepatitis C virus or a humanretrovirus). The method includes administering to a subject in needthereof an effective amount of a compound of Formula (I) therebytreating the subject.

BRIEF DESCRIPTION OF THE DRAWINGS

Not applicable.

DETAILED DESCRIPTION OF THE INVENTION I. Definitions

The abbreviations used herein have their conventional meaning within thechemical and biological arts.

Where moieties are specified by their conventional chemical formulae,written from left to right, they equally encompass the chemicallyidentical moieties that would result from writing the structure fromright to left, e.g., —CH₂O— is equivalent to —OCH₂—.

The term “alkyl,” by itself or as part of another substituent, means,unless otherwise stated, a straight (i.e. unbranched) or branched chain,or cyclic hydrocarbon radical, or combination thereof, which may befully saturated, mono- or polyunsaturated and can include di- andmultivalent radicals, having the number of carbon atoms designated (i.e.C₁-C₁₀ means one to ten carbons). Examples of saturated hydrocarbonradicals include, but are not limited to, groups such as methyl, ethyl,n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, sec-butyl, cyclohexyl,(cyclohexyl)methyl, cyclopropylmethyl, homologs and isomers of, forexample, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like. Anunsaturated alkyl group is one having one or more double bonds or triplebonds. Examples of unsaturated alkyl groups include, but are not limitedto, vinyl, 2-propenyl, crotyl, 2-isopentenyl, 2-(butadienyl),2,4-pentadienyl, 3-(1,4-pentadienyl), ethynyl, 1- and 3-propynyl,3-butynyl, and the higher homologs and isomers.

The term “alkylene” by itself or as part of another substituent means adivalent radical derived from an alkyl, as exemplified, but not limited,by —CH₂CH₂CH₂CH₂—. Typically, an alkyl (or alkylene) group will havefrom 1 to 24 carbon atoms, including those groups having 10 or fewercarbon atoms. A “lower alkyl” or “lower alkylene” is a shorter chainalkyl or alkylene group, generally having eight or fewer carbon atoms.

The terms “alkoxy,” “alkylamino,” and “alkylthio” (or thioalkoxy) areused in their conventional sense, and refer to those alkyl groupsattached to the remainder of the molecule via an oxygen atom, an aminogroup, or a sulfur atom, respectively.

The term “heteroalkyl,” by itself or in combination with another term,means, unless otherwise stated, a stable straight or branched chain, orcyclic hydrocarbon radical, or combinations thereof, consisting of thestated number of carbon atoms and a heteroatom selected from the groupconsisting of O, N, P, Si and S, and wherein the nitrogen and sulfuratoms may optionally be oxidized and the nitrogen heteroatom mayoptionally be quaternized. The heteroatom(s) 0, N, P and S and Si may beplaced at any interior position of the heteroalkyl group or at theposition at which the alkyl group is attached to the remainder of themolecule. Examples include, but are not limited to, —CH₂—CH₂—O—CH₃,—CH₂—CH₂—NH—CH₃, —CH₂—CH₂—N(CH₃)—CH₃, —CH₂—S—CH₂—CH₃, —CH₂—CH₂,—S(O)—CH₃, —CH₂—CH₂—S(O)₂—CH₃, —CH═CH—O—CH₃, —Si(CH₃)₃, —CH₂—CH═N—OCH₃,—CH═CH—N(CH₃)—CH₃, O—CH₃, —O—CH₂—CH₃, and —CN. Up to two heteroatoms maybe consecutive, such as, for example, —CH₂—NH—OCH₃ and —CH₂—O—Si(CH₃)₃.Similarly, the term “heteroalkylene” by itself or as part of anothersubstituent means a divalent radical derived from heteroalkyl, asexemplified, but not limited by, —CH₂—CH₂—S—CH₂—CH₂— and—CH₂—S—CH₂—CH₂—NH—CH₂—. For heteroalkylene groups, heteroatoms can alsooccupy either or both of the chain termini (e.g., alkyleneoxy,alkylenedioxy, alkyleneamino, alkylenediamino, and the like). Stillfurther, for alkylene and heteroalkylene linking groups, no orientationof the linking group is implied by the direction in which the formula ofthe linking group is written. For example, the formula —C(O)₂R′—represents both —C(O)₂R′— and —R′C(O)₂—. As described above, heteroalkylgroups, as used herein, include those groups that are attached to theremainder of the molecule through a heteroatom, such as —C(O)R′,—C(O)NR′, —NR′R″, —OR′, —SR′, and/or —SO₂R′. Where “heteroalkyl” isrecited, followed by recitations of specific heteroalkyl groups, such as—NR′R″ or the like, it will be understood that the terms heteroalkyl and—NR′R″ are not redundant or mutually exclusive. Rather, the specificheteroalkyl groups are recited to add clarity. Thus, the term“heteroalkyl” should not be interpreted herein as excluding specificheteroalkyl groups, such as —NR′R″ or the like.

The terms “cycloalkyl” and “heterocycloalkyl”, by themselves or incombination with other terms, represent, unless otherwise stated, cyclicversions of “alkyl” and “heteroalkyl”, respectively. Additionally, forheterocycloalkyl, a heteroatom can occupy the position at which theheterocycle is attached to the remainder of the molecule. Examples ofcycloalkyl include, but are not limited to, cyclopentyl, cyclohexyl,1-cyclohexenyl, 3-cyclohexenyl, cycloheptyl, and the like. Examples ofheterocycloalkyl include, but are not limited to,1-(1,2,5,6-tetrahydropyridyl), 1-piperidinyl, 2-piperidinyl,3-piperidinyl, 4-morpholinyl, 3-morpholinyl, tetrahydrofuran-2-yl,tetrahydrofuran-3-yl, tetrahydrothien-2-yl, tetrahydrothien-3-yl,1-piperazinyl, 2-piperazinyl, and the like.

The terms “halo” or “halogen,” by themselves or as part of anothersubstituent, mean, unless otherwise stated, a fluorine, chlorine,bromine, or iodine atom. Additionally, terms such as “haloalkyl,” aremeant to include monohaloalkyl and polyhaloalkyl. For example, the term“halo(C₁-C₄)alkyl” is meant to include, but not be limited to,trifluoromethyl, 2,2,2-trifluoroethyl, 4-chlorobutyl, 3-bromopropyl, andthe like.

The term “aryl” means, unless otherwise stated, a polyunsaturated,aromatic, hydrocarbon substituent which can be a single ring or multiplerings (preferably from 1 to 3 rings) which are fused together or linkedcovalently. The term “heteroaryl” refers to aryl groups (or rings) thatcontain from one to four heteroatoms selected from N, O, and S, whereinthe nitrogen and sulfur atoms are optionally oxidized, and the nitrogenatom(s) are optionally quaternized. A heteroaryl group can be attachedto the remainder of the molecule through a carbon or heteroatom.Non-limiting examples of aryl and heteroaryl groups include phenyl,1-naphthyl, 2-naphthyl, 4-biphenyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl,3-pyrazolyl, 2-imidazolyl, 4-imidazolyl, pyrazinyl, 2-oxazolyl,4-oxazolyl, 2-phenyl-4-oxazolyl, 5-oxazolyl, 3-isoxazolyl, 4-isoxazolyl,5-isoxazolyl, 2-thiazolyl, 4-thiazolyl, 5-thiazolyl, 2-furyl, 3-furyl,2-thienyl, 3-thienyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrimidyl,4-pyrimidyl, 5-benzothiazolyl, purinyl, 2-benzimidazolyl, 5-indolyl,1-isoquinolyl, 5-isoquinolyl, 2-quinoxalinyl, 5-quinoxalinyl,3-quinolyl, and 6-quinolyl. Substituent moieties for each of the abovenoted aryl and heteroaryl ring systems may be selected from the group ofacceptable substituent moieties described below.

For brevity, the term “aryl” when used in combination with other terms(e.g., aryloxy, arylthioxy, arylalkyl) includes both aryl and heteroarylrings as defined above. Thus, the term “arylalkyl” is meant to includethose radicals in which an aryl group is attached to an alkyl group(e.g., benzyl, phenethyl, pyridylmethyl and the like) including thosealkyl groups in which a carbon atom (e.g., a methylene group) has beenreplaced by, for example, an oxygen atom (e.g., phenoxymethyl,2-pyridyloxymethyl, 3-(1-naphthyloxy)propyl, and the like).

The term “oxo” as used herein means an oxygen that is double bonded to acarbon atom.

Each of the above terms (e.g., “alkyl,” “heteroalkyl,” “aryl” and“heteroaryl”) are meant to include both substituted and unsubstitutedforms of the indicated radical. Preferred substituent moieties for eachtype of radical are provided below.

Substituent moieties for the alkyl and heteroalkyl radicals (includingthose groups often referred to as alkylene, alkenyl, heteroalkylene,heteroalkenyl, alkynyl, cycloalkyl, heterocycloalkyl, cycloalkenyl, andheterocycloalkenyl) can be one or more of a variety of groups selectedfrom, but not limited to: —OR′, ═O, ═NR′, —NR′R″, —SR′, -halogen,—SiR′R″R′″, —OC(O)R′, —C(O)R′, —CO₂R′, —CONR′R″, —OC(O)NR′R″,—NR″C(O)R′, —NR′—C(O)NR″R′″, —NR″C(O)₂R′, —NR—C(NR′R″R′″)═NR″″,—NR—C(NR′R″)═NR′″, —S(O)R′, —S(O)₂R′, —S(O)₂NR′R″, —NRSO₂R′, —CN and—NO₂ in a number ranging from zero to (2m′+1), where m′ is the totalnumber of carbon atoms in such radical. R′, R″, R′″ and R″″ eachpreferably independently refer to hydrogen, substituted or unsubstitutedheteroalkyl, substituted or unsubstituted cycloalkyl, substituted orunsubstituted heterocycloalkyl, substituted or unsubstituted aryl (e.g.,aryl substituted with 1-3 halogens), substituted or unsubstituted alkyl,alkoxy or thioalkoxy groups, or arylalkyl groups. When a compound of theinvention includes more than one R group, for example, each of the Rgroups is independently selected as are each R′, R″, R″ and R″″ groupswhen more than one of these groups is present. When R′ and R″ areattached to the same nitrogen atom, they can be combined with thenitrogen atom to form a 4-, 5-, 6-, or 7-membered ring. For example,—NR′R″ is meant to include, but not be limited to, 1-pyrrolidinyl and4-morpholinyl. From the above discussion of substituent moieties, one ofskill in the art will understand that the term “alkyl” is meant toinclude groups including carbon atoms bound to groups other thanhydrogen groups, such as haloalkyl (e.g., —CF₃ and —CH₂CF₃) and acyl(e.g., —C(O)CH₃, —C(O)CF₃, —C(O)CH₂OCH₃, and the like).

Similar to the substituent moieties described for the alkyl radical,substituent moieties for the aryl and heteroaryl groups are varied andmay be selected from, for example: halogen, —OR′, —NR′R″, —SR′,-halogen, —SiR′R″R′″, —OC(O)R′, —C(O)R′, —CO₂R′, —CONR′R″, —OC(O)NR′R″,—NR″C(O)R′, —NR′—C(O)NR″R′″, —NR″C(O)₂R′, —NR—C(NR′R″R′″)═NR″″,—NR—C(NR′R″)═NR′″, —S(O)R′, —S(O)₂R′, —S(O)₂NR′R″, —NRSO₂R′, —CN and—NO₂, —R′, —N₃, —CH(Ph)₂, fluoro(C₁-C₄)alkoxy, and fluoro(C₁-C₄)alkyl,in a number ranging from zero to the total number of open valences onthe aromatic ring system; and where R′, R″, R′″ and R″″ are preferablyindependently selected from hydrogen, substituted or unsubstitutedalkyl, substituted or unsubstituted heteroalkyl, substituted orunsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl,substituted or unsubstituted aryl and substituted or unsubstitutedheteroaryl. When a compound of the invention includes more than one Rgroup, for example, each of the R groups is independently selected asare each R′, R″, R″ and R″″ groups when more than one of these groups ispresent.

Two of the substituent moieties on adjacent atoms of the aryl orheteroaryl ring may optionally form a ring of the formula-Q′-C(O)—(CRR′)_(q)-Q″-, wherein Q′ and Q″ are independently —NR—, —O—,—CRR′— or a single bond, and q is an integer of from 0 to 3.Alternatively, two of the substituent moieties on adjacent atoms of thearyl or heteroaryl ring may optionally be replaced with a substituent ofthe formula -A-(CH₂)_(r)—B—, wherein A and B are independently —CRR′—,—O—, —S—, —S(O)—, —S(O)₂—, —S(O)₂NR′— or a single bond, and r is aninteger of from 1 to 4. One of the single bonds of the new ring soformed may optionally be replaced with a double bond. Alternatively, twoof the substituent moieties on adjacent atoms of the aryl or heteroarylring may optionally be replaced with a substituent of the formula—(CRR′)_(s)—X′—(C″R′″)_(d)—, where s and d are independently integers offrom 0 to 3, and X′ is —O—, —S—, —S(O)—, —S(O)₂—, or —S(O)₂NR′—. Thesubstituent moieties R, R′, R″ and R″ are preferably independentlyselected from hydrogen, substituted or unsubstituted alkyl, substitutedor unsubstituted cycloalkyl, substituted or unsubstitutedheterocycloalkyl, substituted or unsubstituted aryl, and substituted orunsubstituted heteroaryl.

As used herein, the term “heteroatom” or “ring heteroatom” is meant toinclude oxygen (O), nitrogen (N), sulfur (S), phosphorus (P), andsilicon (Si).

The term “pharmaceutically acceptable salts” is meant to include saltsof the active compounds which are prepared with relatively nontoxicacids or bases, depending on the particular substituent moieties foundon the compounds described herein. When compounds of the presentinvention contain relatively acidic functionalities, base addition saltscan be obtained by contacting the neutral form of such compounds with asufficient amount of the desired base, either neat or in a suitableinert solvent. Examples of pharmaceutically acceptable base additionsalts include sodium, potassium, calcium, ammonium, organic amino, ormagnesium salt, or a similar salt. When compounds of the presentinvention contain relatively basic functionalities, acid addition saltscan be obtained by contacting the neutral form of such compounds with asufficient amount of the desired acid, either neat or in a suitableinert solvent. Examples of pharmaceutically acceptable acid additionsalts include those derived from inorganic acids like hydrochloric,hydrobromic, nitric, carbonic, monohydrogencarbonic, phosphoric,monohydrogenphosphoric, dihydrogenphosphoric, sulfuric,monohydrogensulfuric, hydriodic, or phosphorous acids and the like, aswell as the salts derived from relatively nontoxic organic acids likeacetic, propionic, isobutyric, maleic, malonic, benzoic, succinic,suberic, fumaric, lactic, mandelic, phthalic, benzenesulfonic,p-tolylsulfonic, citric, tartaric, methanesulfonic, and the like. Alsoincluded are salts of amino acids such as arginate and the like, andsalts of organic acids like glucuronic or galactunoric acids and thelike (see, for example, Berge et al., “Pharmaceutical Salts”, Journal ofPharmaceutical Science, 1977, 66, 1-19). Certain specific compounds ofthe present invention contain both basic and acidic functionalities thatallow the compounds to be converted into either base or acid additionsalts.

The neutral forms of the compounds are preferably regenerated bycontacting the salt with a base or acid and isolating the parentcompound in the conventional manner. The parent form of the compounddiffers from the various salt forms in certain physical properties, suchas solubility in polar solvents.

In addition to salt forms, the present invention provides compounds,which are in a prodrug form. Prodrugs of the compounds described hereinare those compounds that readily undergo chemical changes underphysiological conditions to provide the compounds of the presentinvention. Additionally, prodrugs can be converted to the compounds ofthe present invention by chemical or biochemical methods in an ex vivoenvironment. For example, prodrugs can be slowly converted to thecompounds of the present invention when placed in a transdermal patchreservoir with a suitable enzyme or chemical reagent.

Certain compounds of the present invention can exist in unsolvated formsas well as solvated forms, including hydrated forms. In general, thesolvated forms are equivalent to unsolvated forms and are encompassedwithin the scope of the present invention. Certain compounds of thepresent invention may exist in multiple crystalline or amorphous forms.In general, all physical forms are equivalent for the uses contemplatedby the present invention and are intended to be within the scope of thepresent invention.

Certain compounds of the present invention possess asymmetric carbonatoms (optical centers) or double bonds; the racemates, diastereomers,tautomers, geometric isomers and individual isomers are encompassedwithin the scope of the present invention. The compounds of the presentinvention do not include those which are known in the art to be toounstable to synthesize and/or isolate.

The compounds of the present invention may also contain unnaturalproportions of atomic isotopes at one or more of the atoms thatconstitute such compounds. For example, the compounds may beradiolabeled with radioactive isotopes, such as for example tritium(³H), iodine-125 (¹²⁵I) or carbon-14 (¹⁴C). All isotopic variations ofthe compounds of the present invention, whether radioactive or not, areencompassed within the scope of the present invention.

In some embodiments, each substituted aryl and/or heterocycloalkyl issubstituted with a substituent group, a size limited substituent group,or a lower substituent group. A “substituent group,” as used herein,means a group selected from the following moieties:

-   (A) —OH, —NH₂, —SH, —CN, —CF₃, oxo, halogen, unsubstituted alkyl,    unsubstituted heteroalkyl, unsubstituted cycloalkyl, unsubstituted    heterocycloalkyl, unsubstituted aryl, unsubstituted heteroaryl, and-   (B) alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and    heteroaryl, substituted with at least one substituent selected from:    -   (i) oxy, —OH, —SH, —CN, —CF₃, halogen, unsubstituted alkyl,        unsubstituted heteroalkyl, unsubstituted cycloalkyl,        unsubstituted heterocycloalkyl, unsubstituted aryl,        unsubstituted heteroaryl, and    -   (ii) alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl, and        heteroaryl, substituted with at least one substituent selected        from:        -   (a) oxy, —OH, —NH₂, —SH, —CN, —CF₃, halogen, unsubstituted            alkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,            unsubstituted heterocycloalkyl, unsubstituted aryl,            unsubstituted heteroaryl, and        -   (b) alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl,            or heteroaryl, substituted with at least one substituent            selected from oxy, —OH, —NH₂, —SH, —CN, —CF₃, halogen,            unsubstituted alkyl, unsubstituted heteroalkyl,            unsubstituted cycloalkyl, unsubstituted heterocycloalkyl,            unsubstituted aryl, and unsubstituted heteroaryl.

A “size-limited substituent” or “size-limited substituent group,” asused herein means a group selected from all of the substituentsdescribed above for a “substituent group,” wherein each substituted orunsubstituted alkyl is a substituted or unsubstituted C₁-C₂₀ alkyl, eachsubstituted or unsubstituted heteroalkyl is a substituted orunsubstituted 2 to 20 membered heteroalkyl, each substituted orunsubstituted cycloalkyl is a substituted or unsubstituted C₄-C₈cycloalkyl, and each substituted or unsubstituted heterocycloalkyl is asubstituted or unsubstituted 4 to 8 membered heterocycloalkyl.

A “lower substituent” or “lower substituent group,” as used herein meansa group selected from all of the substituents described above for a“substituent group,” wherein each substituted or unsubstituted alkyl isa substituted or unsubstituted C₁-C₈ alkyl, each substituted orunsubstituted heteroalkyl is a substituted or unsubstituted 2 to 8membered heteroalkyl, each substituted or unsubstituted cycloalkyl is asubstituted or unsubstituted C₅-C₇ cycloalkyl, and each substituted orunsubstituted heterocycloalkyl is a substituted or unsubstituted 5 to 7membered heterocycloalkyl.

The term “treating” refers to any indicia of success in the treatment oramelioration of an injury, pathology or condition, including anyobjective or subjective parameter such as abatement; remission;diminishing of symptoms or making the injury, pathology or conditionmore tolerable to the patient; slowing in the rate of degeneration ordecline; making the final point of degeneration less debilitating;improving a patient's physical or mental well-being, and the like. Thetreatment or amelioration of symptoms can be based on objective orsubjective parameters; including the results of a physical examination,laboratory tests, and the like. For example, the methods describedherein may be used to treat the symptoms of a viral infection.

As used herein, “nucleic acid” means single stranded DNA, RNA andderivative thereof. Modifications include, but are not limited to, thosewhich provide other chemical groups that incorporate additional charge,polarizability, hydrogen bonding, electrostatic interaction, andfunctionality to the nucleic acid ligand bases or to the nucleic acidligand as a whole. Such modifications include, but are not limited to,phosphodiester group modifications (e.g., phosphorothioates,methylphosphonates), 2′-position sugar modifications, 5-positionpyrimidine modifications, 8-position purine modifications, modificationsat exocyclic amines, substitution of 4-thiouridine, substitution of5-bromo or 5-iodo-uracil; backbone modifications, methylations, unusualbase-pairing combinations such as the isobases isocytidine andisoguanidine and the like. Modifications can also include 3′ and 5′modifications such as capping moieties. A 2′-deoxy nucleic acid linkeris a divalent nucleic acid compound of any appropriate length and/orinternucleotide linkage wherein the nucleotides are 2′-deoxynucleotides.

Solid and dashed wedge bonds indicate stereochemistry as customary inthe art. A “squiggle” bond (i.e., “

”) indicates either R- or S-stereochemistry.

II. Compositions

In a first aspect, there is provided a compound having the structure ofFormula (I), or pharmaceutically accepted salt or solvate thereof:

With reference to Formula (I), B^(N) is a substituted or unsubstitutednucleobase. L¹ is a bond or —O—. R¹ is halogen, —CF₃, substituted orunsubstituted alkyl, substituted or unsubstituted cycloalkyl, orsubstituted or unsubstituted aryl. In some embodiments, if L¹ is a bond,then R¹ is halogen. In some embodiments, if L¹ is —O—, then R¹ is —CF₃,substituted or unsubstituted alkyl, substituted or unsubstitutedcycloalkyl, or substituted or unsubstituted aryl. R² is a permeabilityenhancing moiety, a phosphate, or a diphosphate.

As used herein, the term “nucleobase” refers to a moiety as generallyknown in the nucleic acid arts which can function as the base portion ofa nucleic acid. A nucleobase is a portion of a nucleic acid involved inhybridization (base pairing), and includes, but is not limited tonitrogenous bases such as adenine, guanine, thymine, uracil, cytosine,2,6-diaminopurine, and the like. The term “hybridization” is used hereinin its conventional sense and refers generally to the pairing ofcomplementary strands of nucleic acids, including triple-strandednucleic acid hybridization.

In some embodiments, B^(N) is substituted or unsubstituted thymine,substituted or unsubstituted guanine, substituted or unsubstitutedcytosine, substituted or unsubstituted uracil, substituted orunsubstituted 2,6 diaminopurine, substituted or unsubstituted,substituted or unsubstituted methoxypurine, or substituted orunsubstituted 6-O-methylguanine. A person of ordinary skill in the artwill immediately understand that, when referring to a nucleobase(B^(N)), such as guanine, that the nucleobase is attached to theremainder of the molecule of Formula I (or embodiments thereof) and,therefore, exists as a monovalent moiety. In some embodiments, B^(N) isunsubstituted adenine, unsubstituted thymine, unsubstituted guanine,unsubstituted cytosine, or unsubstituted uracil.

In some embodiments, B^(N) is substituted adenine, substituted thymine,substituted guanine, substituted cytosine, or substituted uracil. Insome embodiments, B^(N) is 2,6-diaminopurine. In some embodiments, B^(N)is 6-methoxypurine. In some embodiments, B^(N) is 6-O-methylguanine.

In some embodiments, the compound of Formula (I) has the structure ofFormula (Ia) following (wherein L¹ is —O— according to Formula (I)). Insome embodiments of Formula (Ia), R¹ is —CF₃, substituted orunsubstituted alkyl, substituted or unsubstituted cycloalkyl, orsubstituted or unsubstituted aryl.

In some embodiments of Formulae (I) or (Ia), R¹ is unsubstituted alkyl.In some embodiments, R¹ is R⁴-substituted alkyl. R⁴ is —CN, —NH₂, —COOH,—CF₃, —OH, —SH, —CONH₂, halogen, R⁵-substituted or unsubstituted alkyl,R⁵-substituted or unsubstituted heteroalkyl, R⁵-substituted orunsubstituted cycloalkyl, R⁵-substituted or unsubstitutedheterocycloalkyl, R⁵-substituted or unsubstituted aryl, orR⁵-substituted or unsubstituted heteroaryl. In some embodiments R⁴ isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments R⁴ is R⁵-substitutedalkyl, R⁵-substituted heteroalkyl, R⁵-substituted cycloalkyl,R⁵-substituted heterocycloalkyl, R⁵-substituted aryl, or R⁵-substitutedheteroaryl. R⁵ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen,R⁶-substituted or unsubstituted alkyl, R⁶-substituted or unsubstitutedheteroalkyl, R⁶-substituted or unsubstituted cycloalkyl, R⁶-substitutedor unsubstituted heterocycloalkyl, R⁶-substituted or unsubstituted aryl,or R⁶-substituted or unsubstituted heteroaryl. In some embodiments, R⁵is unsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R⁵ is R⁶-substitutedalkyl, R⁶-substituted heteroalkyl, R⁶-substituted cycloalkyl,R⁶-substituted heterocycloalkyl, R⁶-substituted aryl, or R⁶-substitutedheteroaryl. R⁶ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen,unsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl.

In some embodiments, R¹ is unsubstituted cycloalkyl. In someembodiments, R¹ is R⁷-substituted cycloalkyl. R⁷ is —CN, —NH₂, —COOH,—CF₃, —OH, —SH, —CONH₂, halogen, R⁸-substituted or unsubstituted alkyl,R⁸-substituted or unsubstituted heteroalkyl, R⁸-substituted orunsubstituted cycloalkyl, R⁸-substituted or unsubstitutedheterocycloalkyl, R⁸-substituted or unsubstituted aryl, orR⁸-substituted or unsubstituted heteroaryl. In some embodiments R⁷ isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments R⁷ is R⁸-substitutedalkyl, R⁸-substituted heteroalkyl, R⁸-substituted cycloalkyl,R⁸-substituted heterocycloalkyl, R⁸-substituted aryl, or R⁸-substitutedheteroaryl. R⁸ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen,R⁹-substituted or unsubstituted alkyl, R⁹-substituted or unsubstitutedheteroalkyl, R⁹-substituted or unsubstituted cycloalkyl, R⁹-substitutedor unsubstituted heterocycloalkyl, R⁹-substituted or unsubstituted aryl,or R⁹-substituted or unsubstituted heteroaryl. In some embodiments, R⁸is unsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R⁸ is R⁹-substitutedalkyl, R⁹-substituted heteroalkyl, R⁹-substituted cycloalkyl,R⁹-substituted heterocycloalkyl, R⁹-substituted aryl, or R⁹-substitutedheteroaryl. R⁹ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen,unsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl.

In some embodiments, R¹ is unsubstituted aryl. In some embodiments, R¹is R¹⁰-substituted aryl. R¹⁰ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R¹¹-substituted or unsubstituted alkyl, R¹¹-substitutedor unsubstituted heteroalkyl, R¹¹-substituted or unsubstitutedcycloalkyl, R¹¹-substituted or unsubstituted heterocycloalkyl,R¹¹-substituted or unsubstituted aryl, or R¹¹-substituted orunsubstituted heteroaryl. In some embodiments R¹⁰ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments R¹⁰ is R¹¹-substituted alkyl,R¹¹-substituted heteroalkyl, R¹¹-substituted cycloalkyl, R¹¹-substitutedheterocycloalkyl, R¹¹-substituted aryl, or R¹¹-substituted heteroaryl.R¹¹ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen,R¹²-substituted or unsubstituted alkyl, R¹²-substituted or unsubstitutedheteroalkyl, R¹²-substituted or unsubstituted cycloalkyl,R¹²-substituted or unsubstituted heterocycloalkyl, R¹²-substituted orunsubstituted aryl, or R¹²-substituted or unsubstituted heteroaryl. Insome embodiments, R¹¹ is unsubstituted alkyl, unsubstituted heteroalkyl,unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstitutedaryl, or unsubstituted heteroaryl. In some embodiments, R¹¹ isR¹²-substituted alkyl, R¹²-substituted heteroalkyl, R¹²-substitutedcycloalkyl, R¹²-substituted heterocycloalkyl, R¹²-substituted aryl, orR¹²-substituted heteroaryl. R¹² is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, unsubstituted alkyl, unsubstituted heteroalkyl,unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstitutedaryl, or unsubstituted heteroaryl.

Further to the compound of Formulae (I) or (Ia), in some embodiments, R¹is substituted (e.g., R⁴-substituted) or unsubstituted C₁-C₂₄ (e.g.,C₁-C₁₀ or C₁-C₃) alkyl. In some embodiments, R¹ is C₁-C₂₄ unsubstitutedalkyl. In some embodiments, R¹ is C₁-C₁₆ unsubstituted alkyl. In someembodiments, R¹ is C₁-C₁₂ unsubstituted alkyl. In some embodiments, R¹is C₁-C₁₀ unsubstituted alkyl. In some embodiments, R¹ is C₁-C₃unsubstituted alkyl. In some embodiments, R¹ is methyl, ethyl orisopropyl. In some embodiments, R¹ is methyl. In some embodiments, R¹ isethyl. In some embodiments, R¹ is isopropyl.

Further to the compound of Formulae (I) or (Ia), in some embodiments, R¹is substituted (e.g., R⁷-substituted) or unsubstituted C₃-C₈ cycloalkyl.In some embodiments, R¹ is C₃-C₈ unsubstituted cycloalkyl.

Further to the compound of Formulae (I) or (Ia), in some embodiments, R¹is unsubstituted aryl. In some embodiments, R¹ is substituted (e.g.,R¹⁰-substituted) or unsubstituted phenyl.

Further to the compound of Formulae (I) or (Ia), in some embodiments, R¹is substituted alkyl. In some embodiments, R¹ is substituted C₁-C₁₀alkyl. In some embodiments, R¹ is haloalkyl. In some embodiments, R¹ ismonohaloalkyl. In some embodiments, R¹ is dihaloalkyl. In someembodiments, R¹ is trihaloalkyl. In some embodiments, R¹ is —CF₃.

In some embodiments of the compound of Formulae (I) or (Ia) wherein R¹is substituted alkyl, substituted C₁-C₁₀ alkyl, substituted cycloalkyl,or substituted aryl, R¹ is alkyl substituted with substituted orunsubstituted aryl. In some embodiments, R¹ is benzyl.

In some embodiments of the compound of Formulae (I) or (Ia) wherein R¹is substituted alkyl, substituted cycloalkyl, or substituted aryl, R¹ issubstituted cycloalkyl. In some embodiments, R¹ is substituted C₃-C₈cycloalkyl.

In some embodiments of the compound of Formulae (I) or (Ia) wherein R¹is substituted alkyl, substituted cycloalkyl, or substituted aryl, R¹ issubstituted aryl. In some embodiments, R¹ is substituted phenyl.

In some embodiments, the compound of Formula (I) has the structure ofFormula (Ib) (i.e., where L¹ is a bond). In some embodiments, R¹ ishalogen:

In some embodiments of the compound of Formulae (I) or (Ib), R¹ isfluoro. In Formula (Ib), B^(N) and R² are as defined above in Formulae(I) and (IA).

Further to the compound with the structure of any of Formulae (I), (Ia)or (Ib), in some embodiments, R² has the structure of Formula (II)following,

-L²-O—R³  (II)

wherein L² is a substituted or unsubstituted alkylene, substituted orunsubstituted cycloalkylene, or substituted or unsubstituted arylene. R³is substituted or unsubstituted alkyl, substituted or unsubstitutedcycloalkyl, or substituted or unsubstituted aryl.

In some embodiments, R³ is unsubstituted alkyl. In some embodiments, R³is substituted (e.g., R¹³-substituted) or unsubstituted C₁-C₂₄ (e.g.,C₁₆-C₂₄ or C₈-C₁₆) alkyl. In some embodiments, R³ is unsubstitutedC₁-C₂₄ alkyl. In some embodiments, R³ is unsubstituted C₈-C₂₄ alkyl. Insome embodiments, R³ is unsubstituted C₁₆-C₂₄ alkyl. In someembodiments, R³ is unsubstituted C₈-C₁₆ alkyl. In some embodiments, R³is unsubstituted C₈-C₁₈ alkyl. In some embodiments, R³ is substituted(e.g., R¹³-substituted) or unsubstituted C₁, C₂, C₃, C₄, C₅, C₆, C₇, C₈,C₉, C₁₀, C₁₁, C₁₂, C₁₃, C₁₄, C₁₅, C₁₆, C₁₇, C₁₈, C₁₉, C₂₀, C₂₁, C₂₂,C₂₃, or C₂₄ alkyl.

In some embodiments, R³ is R¹³-substituted alkyl. R¹³ is —CN, —NH₂,—COOH, —CF₃, —OH, —SH, —CONH₂, halogen, R¹⁴-substituted or unsubstitutedalkyl, R¹⁴-substituted or unsubstituted heteroalkyl, R¹⁴-substituted orunsubstituted cycloalkyl, R¹⁴-substituted or unsubstitutedheterocycloalkyl, R¹⁴-substituted or unsubstituted aryl, orR¹⁴-substituted or unsubstituted heteroaryl. In some embodiments, R¹³ isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R¹³ is —CN, —NH₂, —COOH,—CF₃, —OH, —SH, —CONH₂, halogen, R¹⁴-substituted alkyl, R¹⁴-substitutedheteroalkyl, R¹⁴-substituted cycloalkyl, R¹⁴-substitutedheterocycloalkyl, R¹⁴-substituted aryl, or R¹⁴ substituted heteroaryl.R¹⁴ is R¹⁵-substituted or unsubstituted alkyl, R¹⁵-substituted orunsubstituted heteroalkyl, R¹⁵-substituted or unsubstituted cycloalkyl,R¹⁵-substituted or unsubstituted heterocycloalkyl, R¹⁵-substituted orunsubstituted aryl, or R¹⁵-substituted or unsubstituted heteroaryl. Insome embodiments, R¹⁴ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂,halogen, unsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R¹⁴ is R¹⁵-substitutedalkyl, R¹⁵-substituted heteroalkyl, R¹⁵-substituted cycloalkyl,R¹⁵-substituted heterocycloalkyl, R¹⁵-substituted aryl, orR¹⁵-substituted heteroaryl. R¹⁵ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, unsubstituted alkyl, unsubstituted heteroalkyl,unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstitutedaryl, or unsubstituted heteroaryl.

In some embodiments, R³ is R¹⁶-substituted cycloalkyl. R¹⁶ is —CN, —NH₂,—COOH, —CF₃, —OH, —SH, —CONH₂, halogen, R¹⁷-substituted or unsubstitutedalkyl, R¹⁷-substituted or unsubstituted heteroalkyl, R¹⁷-substituted orunsubstituted cycloalkyl, R¹⁷-substituted or unsubstitutedheterocycloalkyl, R¹⁷-substituted or unsubstituted aryl, orR¹⁷-substituted or unsubstituted heteroaryl. In some embodiments, R¹⁶ isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R¹⁶ is R¹⁷-substitutedalkyl, R¹⁷-substituted heteroalkyl, R¹⁷-substituted cycloalkyl,R¹⁷-substituted heterocycloalkyl, R¹⁷-substituted aryl, orR¹⁷-substituted heteroaryl. R¹⁷ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R¹⁸-substituted or unsubstituted alkyl, R¹⁸-substitutedor unsubstituted heteroalkyl, R¹⁸-substituted or unsubstitutedcycloalkyl, R¹⁸-substituted or unsubstituted heterocycloalkyl,R¹⁸-substituted or unsubstituted aryl, or R¹⁸-substituted orunsubstituted heteroaryl. In some embodiments, R¹⁷ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments, R¹⁷ is R¹⁸-substituted alkyl,R¹⁸-substituted heteroalkyl, R¹⁸-substituted cycloalkyl, R¹⁸-substitutedheterocycloalkyl, R¹⁸-substituted aryl, or R¹⁸-substituted heteroaryl.R¹⁸ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen, unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl.

In some embodiments, R³ is R¹⁹-substituted aryl. R¹⁹ is —CN, —NH₂,—COOH, —CF₃, —OH, —SH, —CONH₂, halogen, R²⁰-substituted or unsubstitutedalkyl, R²⁰-substituted or unsubstituted heteroalkyl, R²⁰-substituted orunsubstituted cycloalkyl, R²⁰-substituted or unsubstitutedheterocycloalkyl, R²⁰-substituted or unsubstituted aryl, orR²⁰-substituted or unsubstituted heteroaryl. In some embodiments, R¹⁹ isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R¹⁹ is R²⁰-substitutedalkyl, R²⁰-substituted heteroalkyl, R²⁰-substituted cycloalkyl,R²⁰-substituted heterocycloalkyl, R²⁰-substituted aryl, orR²⁰-substituted heteroaryl. R²⁰ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R²¹-substituted or unsubstituted alkyl, R²¹-substitutedor unsubstituted heteroalkyl, R²¹-substituted or unsubstitutedcycloalkyl, R²¹-substituted or unsubstituted heterocycloalkyl,R²¹-substituted or unsubstituted aryl, or R²¹-substituted orunsubstituted heteroaryl. In some embodiments, R²⁰ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments, R²⁰ is R²¹-substituted alkyl,R²¹-substituted heteroalkyl, R²¹-substituted cycloalkyl, R²¹-substitutedheterocycloalkyl, R²¹-substituted aryl, or R²¹-substituted heteroaryl.R²¹ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen, unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl.

In some embodiments, L² is substituted (e.g., R²²-substituted) orunsubstituted C₁-C₈ alkylene. In some embodiments, L² is substituted(e.g., R²²-substituted) unsubstituted C₁, C₂, C₃, C₄, C₅, C₆, C₇, or C₈alkylene.

In some embodiments, L² is R²²-substituted alkylene. R²² is —CN, —NH₂,—COOH, —CF₃, —OH, —SH, —CONH₂, halogen, R²³-substituted or unsubstitutedalkyl, R²³-substituted or unsubstituted heteroalkyl, R²³-substituted orunsubstituted cycloalkyl, R²³-substituted or unsubstitutedheterocycloalkyl, 23-substituted or unsubstituted aryl, or23-substituted or unsubstituted heteroaryl. In some embodiments, R²² isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R²² is R²³-substitutedalkyl, R²³-substituted heteroalkyl, R²³-substituted cycloalkyl,R²³-substituted heterocycloalkyl, R²³-substituted aryl, orR²³-substituted heteroaryl. R²³ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R²⁴-substituted or unsubstituted alkyl, R²⁴-substitutedor unsubstituted heteroalkyl, R²⁴-substituted or unsubstitutedcycloalkyl, R²⁴-substituted or unsubstituted heterocycloalkyl,R²⁴-substituted or unsubstituted aryl, or R²⁴-substituted orunsubstituted heteroaryl. In some embodiments, R²³ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments, R²³ is R²⁴-substituted alkyl,R²⁴-substituted heteroalkyl, R²⁴-substituted cycloalkyl, R²⁴-substitutedheterocycloalkyl, R²⁴-substituted aryl, or R²⁴-substituted heteroaryl.R²⁴ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen, unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl.

In some embodiments, L² is R²⁵-substituted cycloalkylene. R²⁵ is —CN,—NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen, R²⁶-substituted orunsubstituted alkyl, R²⁶-substituted or unsubstituted heteroalkyl,R²⁶-substituted or unsubstituted cycloalkyl, R²⁶-substituted orunsubstituted heterocycloalkyl, R²⁶-substituted or unsubstituted aryl,or R²⁶-substituted or unsubstituted heteroaryl. In some embodiments, R²⁵is unsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R²⁵ is R²⁶-substitutedalkyl, R²⁶-substituted heteroalkyl, R²⁶-substituted cycloalkyl,R²⁶-substituted heterocycloalkyl, R²⁶-substituted aryl, orR²⁶-substituted heteroaryl. R²⁶ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R²⁷-substituted or unsubstituted alkyl, R²⁷-substitutedor unsubstituted heteroalkyl, R²⁷-substituted or unsubstitutedcycloalkyl, R²⁷-substituted or unsubstituted heterocycloalkyl,R²⁷-substituted or unsubstituted aryl, or R²⁷-substituted orunsubstituted heteroaryl. In some embodiments, R²⁶ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments, R²⁶ is R²⁷-substituted alkyl,R²⁷-substituted heteroalkyl, R²⁷-substituted cycloalkyl, R²⁷-substitutedheterocycloalkyl, R²⁷-substituted aryl, or R²⁷-substituted heteroaryl.R²⁷ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen, unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl.

In some embodiments, L² is R²⁸-substituted arylene. R²⁸ is —CN, —NH₂,—COOH, —CF₃, —OH, —SH, —CONH₂, halogen, R²⁹-substituted or unsubstitutedalkyl, R²⁹-substituted or unsubstituted heteroalkyl, R²⁹-substituted orunsubstituted cycloalkyl, R²⁹-substituted or unsubstitutedheterocycloalkyl, R²⁹-substituted or unsubstituted aryl, orR²⁹-substituted or unsubstituted heteroaryl. In some embodiments, R²⁸ isunsubstituted alkyl, unsubstituted heteroalkyl, unsubstitutedcycloalkyl, unsubstituted heterocycloalkyl, unsubstituted aryl, orunsubstituted heteroaryl. In some embodiments, R²⁸ is R²⁹-substitutedalkyl, R²⁹-substituted heteroalkyl, R²⁹-substituted cycloalkyl,R²⁹-substituted heterocycloalkyl, R²⁹-substituted aryl, orR²⁹-substituted heteroaryl. R²⁹ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R³⁰-substituted or unsubstituted alkyl, R³⁰-substitutedor unsubstituted heteroalkyl, R³⁰-substituted or unsubstitutedcycloalkyl, R³⁰-substituted or unsubstituted heterocycloalkyl,R³⁰-substituted or unsubstituted aryl, or R³⁰-substituted orunsubstituted heteroaryl. In some embodiments, R²⁹ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments, R²⁹ is R³⁰-substituted alkyl,R³⁰-substituted heteroalkyl, R³⁰-substituted cycloalkyl, R³⁰-substitutedheterocycloalkyl, R³⁰-substituted aryl, or R³⁰-substituted heteroaryl.R³⁰ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen, unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl.

Further to the compound with the structure of any of Formulae (I), (Ia)or (Ib), or the compound wherein R² has the structure of Formula (II),in some embodiments, R² is octadecyloxyethyl, hexadecyloxyethyl,hexadecyloxypropyl, 15-methyl-hexadecyloxypropyl,15-methyl-hexadecyloxyethyl, 13-methyl-tetradecyloxypropyl,13-methyl-tetradecyloxyethyl, 14-cyclopropyl-tetradecyloxypropyl,14-cyclopropyl-tetradecyloxyethyl, or1-O-octadecyl-2-O-benzyl-sn-glyceryl. In some embodiments, L² is C₁, C₂,C₃, C₄, C₅, C₆, C₇, or C₈ alkylene.

It is understood that some compounds described herein can exist asstereoisomeric forms including e.g., R-, S- and racemic (RS-) forms.Unless expressly indicated otherwise, all stereoisomer forms arecontemplated herein. Accordingly, further to the compound with thestructure of any of Formulae (I), (Ia) or (Ib), wherein R² has thestructure of Formula (II), in some embodiments, the compound has thestructure of one of Formulae (Ia1S) to (Ia7S) following. R¹ and R² inFormulae (Ia1S) to (Ia7S) are as defined above.

In some embodiments, the compound has the structure of one of Formulae(Ia1R) to (Ia7R) following. R¹ and R² in Formulae (Ia1R) to (Ia7R) areas defined above.

In some embodiments, the compound has the structure of one of Formulae(Ia1RS) to (Ia7RS) following. R¹ and R² in Formulae (Ia1RS) to (Ia7RS)are as defined above.

Further to the compound with the structure of Formulae (Ib), in someembodiments, the compound has the structure of one of Formulae (Ib1S) to(Ib7S) following. R¹ and R² in Formulae (Ib1S) to (Ib7S) are as definedabove.

In some embodiments, the compound has the structure of one of Formulae(Ib1R) to (Ib7R) following. R¹ and R² in Formulae (Ib1R) to (Ib7R) areas defined above.

In some embodiments, the compound has the structure of one of Formulae(Ib1RS) to (Ib7RS) following. R¹ and R² in Formulae (Ib1RS) to (Ib7RS)are as defined above.

In some embodiments of the compounds of Formulae I, Ia1S-Ia7S,Ia1R-Ia7R, or Ia1RS-Ia7RS, R₁ is —CF₃, substituted or unsubstitutedC₁-C₁₀ alkyl, substituted or unsubstituted C₃-C₈ cycloalkyl (e.g.cyclopropyl) or substituted or unsubstituted aryl (e.g. benzyl orphenyl). In some embodiments, R₁ is —CF₃, unsubstituted C₁-C₁₀ alkyl,unsubstituted C₃-C₈ cycloalkyl (e.g. cyclopropyl) or unsubstituted aryl(e.g. benzyl or phenyl).

In some embodiments of the compounds of Formula I, R² is a permeabilityenhancing moiety, a phosphate or a diphosphate. In some embodiments, R²is a permeability enhancing moiety. A “permeability enhancing moiety” asused herein refers to a chemical moiety that forms an ester with theoxygen and phosphorus to which it is attached as shown in Formulae I,Ia1S-Ia7S, Ia1R-Ia7R, Ia1RS-Ia7RS, Ib1S-Ib7S, Ib1R-Ib7R, Ib1RS-Ib7RS,and which increases the cell permeability of the compound relative tocompounds in which R² is hydrogen. In some embodiments, permeabilityenhancers act to increase drug absorption through either theparacellular or transcellular pathways. See e.g., Ouyang, H., et al.,2002, J. Med. Chem., 45:2857-2866; Lane, M. E. & Corrigan, O. I., 2006,J. Pharm. Pharmacol., 58:271-275.

In some embodiments, R² is substituted or unsubstituted alkyl,substituted or unsubstituted heteroalkyl, substituted or unsubstitutedcycloalkyl, substituted or unsubstituted heterocycloalkyl, substitutedor unsubstituted aryl, or substituted or unsubstituted heteroaryl. Insome embodiments, R² contains 3-24, 6-24, 9-24, 12-24, 15-24, 18-24, or21-24 carbon atoms. In some embodiments, R² is substituted orunsubstituted C₃ or greater alkyl, or substituted or unsubstituted C₃ orgreater heteroalkyl. In some embodiments, R² is unsubstituted alkyl,unsubstituted heteroalkyl, unsubstituted cycloalkyl, unsubstitutedheterocycloalkyl, unsubstituted aryl, or unsubstituted heteroaryl. Insome embodiments, R² is unsubstituted C₃ or greater alkyl, orunsubstituted C₃ or greater heteroalkyl. In some embodiments, R² isR³¹-substituted alkyl, R³¹-substituted heteroalkyl, R³¹-substitutedcycloalkyl, R³¹-substituted heterocycloalkyl, R³¹-substituted aryl, orR³¹-substituted heteroaryl. R³¹ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, R³²-substituted or unsubstituted alkyl, R³²-substitutedor unsubstituted heteroalkyl, R³²-substituted or unsubstitutedcycloalkyl, R³²-substituted or unsubstituted heterocycloalkyl,R³²-substituted or unsubstituted aryl, or R³²-substituted orunsubstituted heteroaryl. In some embodiments R³¹ is unsubstitutedalkyl, unsubstituted heteroalkyl, unsubstituted cycloalkyl,unsubstituted heterocycloalkyl, unsubstituted aryl, or unsubstitutedheteroaryl. In some embodiments, R³¹ is R³²-substituted alkyl,R³²-substituted heteroalkyl, R³²-substituted cycloalkyl, R³²-substitutedheterocycloalkyl, R³²-substituted aryl, or R³²-substituted heteroaryl.R³² is —CN, —NH₂, —COOH, —CF₃, —OH, —SH, —CONH₂, halogen,R³³-substituted or unsubstituted alkyl, R³³-substituted or unsubstitutedheteroalkyl, R³³-substituted or unsubstituted cycloalkyl,R³³-substituted or unsubstituted heterocycloalkyl, R³³-substituted orunsubstituted aryl, or R³³-substituted or unsubstituted heteroaryl. Insome embodiments, R³² is unsubstituted alkyl, unsubstituted heteroalkyl,unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstitutedaryl, or unsubstituted heteroaryl. In some embodiments, R³² isR³³-substituted alkyl, R³³-substituted heteroalkyl, R³³-substitutedcycloalkyl, R³³-substituted heterocycloalkyl, R³³-substituted aryl, orR³³-substituted heteroaryl. R³³ is —CN, —NH₂, —COOH, —CF₃, —OH, —SH,—CONH₂, halogen, unsubstituted alkyl, unsubstituted heteroalkyl,unsubstituted cycloalkyl, unsubstituted heterocycloalkyl, unsubstitutedaryl, or unsubstituted heteroaryl.

Without wishing to be bound by any theory, it is believed that thelipophilicity of a permeability enhancer can play a major role inpermeability enhancement. In some embodiments, the permeabilityenhancing moiety has the structure of Formula (II),

-L²-O—R³.  (II)

In some embodiments, L² is a substituted or unsubstituted alkylene(e.g., substituted or unsubstituted C₁-C₈ alkylene), substituted orunsubstituted cycloalkylene (substituted or unsubstituted C₃-C₈cycloalkylene), or substituted or unsubstituted arylene. In someembodiments, R³ is substituted or unsubstituted alkyl (e.g. substitutedor unsubstituted C₈-C₂₄ alkyl), substituted or unsubstituted cycloalkyl(e.g. a substituted or unsubstituted C₃-C₈ cycloalkyl), or substitutedor unsubstituted aryl. In some embodiments, -L²-O—R³ includes at least16 atoms. In some embodiments, -L²-O—R³ has 18 to 24 atoms. In certainembodiments, the atoms are linked together in a linear arrangement. Thepermeability enhancing moiety may be octadecyloxyethyl,hexadecyloxyethyl, hexadecyloxypropyl, 15-methyl-hexadecyloxypropyl,15-methyl-hexadecyloxyethyl, 13-methyl-tetradecyloxypropyl,13-methyl-tetradecyloxyethyl, 14-cyclopropyl-tetradecyloxypropyl,14-cyclopropyl-tetradecyloxyethyl, or1-O-octadecyl-2-O-benzyl-sn-glyceryl. Additional exemplary permeabilityenhancing moieties useful in the compounds and methods described hereinare described in U.S. Pat. No. 6,716,825 and U.S. Pat. No. 7,749,983,and US Patent Publication No. US2008-0221061, the contents of which areincorporated herein by reference in their entireties and for allpurposes.

In some embodiments, the novel phosphonate compounds provided herein areless toxic, more active and selective than previously known candidatessuch as ODE-(S)-HPMPA (which includes a hydrogen at the corresponding R¹position) against a variety of viruses, including e.g., hepatitis Cvirus and HIV-1. The retention of antiviral efficacy against HIV and HCVwith marked diminution of cellular toxicity caused by the addition of amethyl group to the side chain of HPMPA is quite unexpected and notobvious. Unmodified MPMPA had an EC₅₀ of 20 μM and a CC₅₀ of 40 μMsuggesting no selective antiviral activity. “EC₅₀” refers, in thecustomary sense, to the concentration required to achieve half-maximaleffect of a compound. “CC₅₀” refers, in the customary sense, to theconcentration required to achieve half maximal cytotoxicity.

In some embodiments, each substituted group described above in thecompounds of Formula I or embodiments thereof is substituted with atleast one substituent group. More specifically, in some embodiments,each substituted alkyl, substituted cycloalkyl, substituted aryl,substituted alkylene substituted cycloalkylene, and/or substitutedarylene, described above in the compounds of Formula I or embodimentsthereof are substituted with at least one substituent group. In otherembodiments, at least one or all of these groups are substituted with atleast one size-limited substituent group. In some embodiments, nosubstituent of Formula I is further substituted.

In some embodiments, a compound is selected from Table 1 following.

TABLE 1

In some embodiments, a compound is selected from Table 2 following.

TABLE 2

In some embodiments, a compound is selected from Table 3 following.

TABLE 3

Exemplary Syntheses

Synthesis of the new ANP analogs can be carried out using a synthonapproach, e.g., the approach developed for alkoxyalkyl esters of(S)-9-[3-hydroxy-2-(phosphonomethoxy)-propyl]adenine [(S)-HPMPA]. Seee.g., Beadle, J. R.; et al., 2006, Id. Exemplary of this approach isScheme 1 (Example 1), wherein adenine can react with various alkylglycidyl ethers under basic conditions to give a series of9-(3-alkoxy-2-hydroxypropyl)adenines, e.g., Cmpds 2-5 (see Examples).After protection of the amino group with monomethoxytrityl, Cmpds 6-9(see Examples) can be alkylated with octadecyloxyethyl orhexadecyloxypropyl p-toluenesulfonyloxymethyl-phosphonate, thendeprotected to provide adenine derivatives Cmpds 15-19 (see Examples).As shown in Schemes 2 and 3 (see Examples), various3-methoxy-2-phosphonomethoxypropyl (MPMP-) analogs of 2,6-diaminopurine(23-26) and guanine (34-37) can be prepared using similar methods.Additional schemes and experimental details for target Cmpds 40, 43 and44 are provided in the Examples.

III. Methods of Use

The compounds provided herein are useful, inter alia, in inhibitingviral replication, including hepatitis C viruses. Examples belowdescribe the synthesis of specific compounds of the invention. Inparticular the compound octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy) propyl]adenine (ODE-(S)-MPMPA) hasbeen tested and found to have potent inhibitory activity in HCV infectedcells and in HIV-1 infected MT-2 cells. ODE-(S)-IPPMPA has beensynthesized but has low activity against HCV. ODE-(S)-MPMPC has beensynthesized and has antiviral activity against HIV-1 infected humanperipheral blood mononuclear cells while hexadecyloxypropyl-(S)-MPMPGhas submicromolar activity.

In another aspect, diphosphate metabolites of the compound of theinvention may inhibit viral RNA-dependent RNA polymerases and thusinhibit the replication of the hepatitis C virus; they also inhibitreplication of HIV-1 in vitro possibly due to inhibition of HIV reversetranscriptase.

Compounds described herein may be useful for treating human patientsinfected with an RNA virus, e.g., rotavirus, coronavirus, picornavirus,calicivirus, flavivirus, togavirus, or hepevirus; a DNA virus, e.g.,herpesvirus, adenovirus, asfarvirus, polyomavirus, or poxvirus; or aretrovirus, e.g., alpharetrovirus, betaretrovirus, gammaretrovirus,deltaretrovirus, epsilonretrovus, lentivirus or spumavirus. Inparticular, compounds described herein may be useful for treating humanpatients infected with the hepatitis C virus or with a human retrovirus,such as HIV-1.

Compounds described herein may be useful for treating human patientsinfected with a disease caused by, or associated with, an RNA virusincluding a retrovirus, or a DNA virus.

In another aspect, the invention also provides processes and novelintermediates disclosed herein which are useful for preparing compoundsof the invention. In other aspects, novel methods for synthesis,analysis, separation, isolation, purification, characterization, andtesting of the compounds of this invention are provided.

In another aspect, a method of inhibiting a viral RNA-dependent RNApolymerase is provided. The method includes contacting a compound ofFormula I or embodiment thereof wherein R² is a permeability enhancingmoiety, or embodiments thereof, with a cell including a viralRNA-dependent RNA polymerase thereby inhibiting said viral RNA-dependentRNA polymerase.

In another aspect, there is provided a method of inhibiting a viralRNA-dependent RNA polymerase. The method includes contacting a viralRNA-dependent RNA polymerase with an effective amount of a compound ofFormula (I) thereby inhibiting the viral RNA-dependent RNA polymerase.

In another aspect, there is provided a method of inhibiting a viralreverse transcriptase. The method includes contacting a viral reversetranscriptase with an effective amount of a compound of Formula (I)thereby inhibiting the viral RNA-dependent RNA polymerase.

In another aspect, a method of inhibiting a viral reverse transcriptaseis provided. The method includes contacting a compound of Formula I orembodiment thereof wherein R² is a permeability enhancing moiety, orembodiments thereof, with a cell including a viral RNA-dependent RNApolymerase thereby inhibiting said viral RNA-dependent RNA polymerase.

In another aspect, a method of inhibiting replication of a hepatitis Cvirus or a human retrovirus is provided. The method includes contactinga compound of Formula I or embodiment thereof wherein R² is apermeability enhancing moiety, or embodiments thereof, with a cellinfected with a hepatitis C virus or a human retrovirus therebyinhibiting replication of said hepatitis C virus or human retrovirus.

In another aspect, a method of inhibiting viral RNA-dependent RNApolymerase is provided. The method includes contacting (e.g. in vitro) acompound of Formula I or embodiment thereof wherein R₂ is a phosphate ordiphosphate, or embodiments thereof, with a viral RNA-dependent RNApolymerase thereby inhibiting said viral RNA-dependent RNA polymerase.

In another aspect, a method of inhibiting viral reverse transcriptase isprovided. The method includes contacting (e.g. in vitro) a compound ofFormula I or embodiment thereof wherein R² is a phosphate ordiphosphate, or embodiments thereof, with a reverse transcriptasethereby inhibiting said reverse transcriptase.

IV. Methods of Treating Disease

In another aspect, a method of treating a subject infected with ahepatitis C virus or a human retrovirus is provided. The method includesadministering to a subject in need thereof an effective amount of acompound of Formula I or embodiment thereof wherein R² is a permeabilityenhancing moiety, or embodiments thereof. Diseases contemplated in thepractice of the methods disclosed herein include diseases related to RNAviruses, e.g., SARS, poliomyelitis, the common cold, hepatitis A, yellowfever, West Nile Fever, West Nile meningitis, hepatitis C, Dengue fever,rubella, Ross River fever, sindbis fever, Chikungunya arthralgicdisease, hepatitis E, Borna disease, Ebola hemorrhagic fever, Marburghemorrhagic fever, measles, mumps, rabies, Lassa fever, Crimean-Congohemorrhagic fever, and influenza. Additional diseases include thoserelated to retroviruses, e.g., HIV, and diseases related to DNA viruses,e.g., herpes simplex, varicella zoster, African swine fever, cowpox,smallpox, hepatitis B, and progressive multifocal leukoencephalopathy,

V. Pharmaceutical Compositions

In another aspect, the present invention provides pharmaceuticalcompositions. The pharmaceutical composition includes a pharmaceuticallyacceptable excipient and a compound of the present invention (e.g.Formula I or embodiments thereof)).

The pharmaceutical compositions described herein are typically used totreat a disorder or condition using known methods of nucleic acidpharmaceutical antiviral therapies.

In an exemplary embodiment, the pharmaceutical composition includes from1 μg to 2000 mg of a compound disclosed herein, e.g., 1 μg to 1 mg, 1 mgto 10 mg, 1 mg to 100 mg, 1 mg to 1000 mg, 1 mg to 1500 mg, or even 1 mgto 2000 mg.

A. Formulations

The compounds of the present invention can be prepared and administeredin a wide variety of oral, parenteral and topical dosage forms. Oralpreparations include tablets, pills, powder, dragees, capsules, liquids,lozenges, gels, syrups, slurries, suspensions, etc., suitable foringestion by the patient. The compounds of the present invention canalso be administered by injection, that is, intravenously,intramuscularly, intracutaneously, subcutaneously, intraduodenally, orintraperitoneally. Also, the compounds described herein can beadministered by inhalation, for example, intranasally. Additionally, thecompounds of the present invention can be administered transdermally.The compounds of the present invention can also be administered by inintraocular, intravaginal, and intrarectal routes includingsuppositories, insufflation, powders and aerosol formulations (forexamples of steroid inhalants, see Rohatagi, J. Clin. Pharmacol.35:1187-1193, 1995; Tjwa, Ann. Allergy Asthma Immunol. 75:107-111,1995). Thus, the pharmaceutical compositions described herein may beadapted for oral administration. In some embodiments, the pharmaceuticalcomposition is in the form of a tablet. Moreover, the present inventionprovides pharmaceutical compositions including a pharmaceuticallyacceptable carrier or excipient and either a compound of the presentinvention, or a pharmaceutically acceptable salt of a compound of thepresent invention.

For preparing pharmaceutical compositions from the compounds of thepresent invention, pharmaceutically acceptable carriers can be eithersolid or liquid. Solid form preparations include powders, tablets,pills, capsules, cachets, suppositories, and dispersible granules. Asolid carrier can be one or more substances, which may also act asdiluents, flavoring agents, binders, preservatives, tabletdisintegrating agents, or an encapsulating material. Details ontechniques for formulation and administration are well described in thescientific and patent literature, see, e.g., the latest edition ofREMINGTON'S PHARMACEUTICAL SCIENCES, Maack Publishing Co, Easton Pa.(“Remington's”).

In powders, the carrier is a finely divided solid, which is in a mixturewith the finely divided active component. In tablets, the activecomponent is mixed with the carrier having the necessary bindingproperties in suitable proportions and compacted in the shape and sizedesired.

The powders and tablets preferably contain from 5% or 10% to 70% of theactive compound. Suitable carriers are magnesium carbonate, magnesiumstearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin,tragacanth, methylcellulose, sodium carboxymethylcellulose, a lowmelting wax, cocoa butter, and the like. The term “preparation” isintended to include the formulation of the active compound withencapsulating material as a carrier providing a capsule in which theactive component with or without other carriers, is surrounded by acarrier, which is thus in association with it. Similarly, cachets andlozenges are included. Tablets, powders, capsules, pills, cachets, andlozenges can be used as solid dosage forms suitable for oraladministration.

Suitable solid excipients are carbohydrate or protein fillers include,but are not limited to sugars, including lactose, sucrose, mannitol, orsorbitol; starch from corn, wheat, rice, potato, or other plants;cellulose such as methyl cellulose, hydroxypropylmethyl-cellulose, orsodium carboxymethylcellulose; and gums including arabic and tragacanth;as well as proteins such as gelatin and collagen. If desired,disintegrating or solubilizing agents may be added, such as thecross-linked polyvinyl pyrrolidone, agar, alginic acid, or a saltthereof, such as sodium alginate.

Dragee cores are provided with suitable coatings such as concentratedsugar solutions, which may also contain gum arabic, talc,polyvinylpyrrolidone, carbopol gel, polyethylene glycol, and/or titaniumdioxide, lacquer solutions, and suitable organic solvents or solventmixtures. Dyestuffs or pigments may be added to the tablets or drageecoatings for product identification or to characterize the quantity ofactive compound (i.e., dosage). Pharmaceutical preparations of theinvention can also be used orally using, for example, push-fit capsulesmade of gelatin, as well as soft, sealed capsules made of gelatin and acoating such as glycerol or sorbitol. Push-fit capsules can containcompounds of Formulae I or II mixed with a filler or binders such aslactose or starches, lubricants such as talc or magnesium stearate, and,optionally, stabilizers. In soft capsules, the compounds may bedissolved or suspended in suitable liquids, such as fatty oils, liquidparaffin, or liquid polyethylene glycol with or without stabilizers.

For preparing suppositories, a low melting wax, such as a mixture offatty acid glycerides or cocoa butter, is first melted and the activecomponent is dispersed homogeneously therein, as by stirring. The moltenhomogeneous mixture is then poured into convenient sized molds, allowedto cool, and thereby to solidify.

Liquid form preparations include solutions, suspensions, and emulsions,for example, water or water/propylene glycol solutions. For parenteralinjection, liquid preparations can be formulated in solution in aqueouspolyethylene glycol solution.

Aqueous solutions suitable for oral use can be prepared by dissolvingthe active component in water and adding suitable colorants, flavors,stabilizers, and thickening agents as desired. Aqueous suspensionssuitable for oral use can be made by dispersing the finely dividedactive component in water with viscous material, such as natural orsynthetic gums, resins, methylcellulose, sodium carboxymethylcellulose,hydroxypropylmethylcellulose, sodium alginate, polyvinylpyrrolidone, gumtragacanth and gum acacia, and dispersing or wetting agents such as anaturally occurring phosphatide (e.g., lecithin), a condensation productof an alkylene oxide with a fatty acid (e.g., polyoxyethylene stearate),a condensation product of ethylene oxide with a long chain aliphaticalcohol (e.g., heptadecaethylene oxycetanol), a condensation product ofethylene oxide with a partial ester derived from a fatty acid and ahexitol (e.g., polyoxyethylene sorbitol mono-oleate), or a condensationproduct of ethylene oxide with a partial ester derived from fatty acidand a hexitol anhydride (e.g., polyoxyethylene sorbitan mono-oleate).The aqueous suspension can also contain one or more preservatives suchas ethyl or n-propyl p-hydroxybenzoate, one or more coloring agents, oneor more flavoring agents and one or more sweetening agents, such assucrose, aspartame or saccharin. Formulations can be adjusted forosmolarity.

Also included are solid form preparations, which are intended to beconverted, shortly before use, to liquid form preparations for oraladministration. Such liquid forms include solutions, suspensions, andemulsions. These preparations may contain, in addition to the activecomponent, colorants, flavors, stabilizers, buffers, artificial andnatural sweeteners, dispersants, thickeners, solubilizing agents, andthe like.

Oil suspensions can be formulated by suspending a compound in avegetable oil, such as arachis oil, olive oil, sesame oil or coconutoil, or in a mineral oil such as liquid paraffin; or a mixture of these.The oil suspensions can contain a thickening agent, such as beeswax,hard paraffin or cetyl alcohol. Sweetening agents can be added toprovide a palatable oral preparation, such as glycerol, sorbitol orsucrose. These formulations can be preserved by the addition of anantioxidant such as ascorbic acid. As an example of an injectable oilvehicle, see Minto, J. Pharmacol. Exp. Ther. 281:93-102, 1997. Thepharmaceutical formulations of the invention can also be in the form ofoil-in-water emulsions. The oily phase can be a vegetable oil or amineral oil, described above, or a mixture of these. Suitableemulsifying agents include naturally-occurring gums, such as gum acaciaand gum tragacanth, naturally occurring phosphatides, such as soybeanlecithin, esters or partial esters derived from fatty acids and hexitolanhydrides, such as sorbitan mono-oleate, and condensation products ofthese partial esters with ethylene oxide, such as polyoxyethylenesorbitan mono-oleate. The emulsion can also contain sweetening agentsand flavoring agents, as in the formulation of syrups and elixirs. Suchformulations can also contain a demulcent, a preservative, or a coloringagent.

The compounds can be delivered by transdermally, by a topical route,formulated as applicator sticks, solutions, suspensions, emulsions,gels, creams, ointments, pastes, jellies, paints, powders, and aerosols.

The compounds can also be delivered as microspheres for slow release inthe body. For example, microspheres can be administered via intradermalinjection of drug-containing microspheres, which slowly releasesubcutaneously (see Rao, J. Biomater Sci. Polym. Ed. 7:623-645, 1995; asbiodegradable and injectable gel formulations (see, e.g., Gao Pharm.Res. 12:857-863, 1995); or, as microspheres for oral administration(see, e.g., Eyles, J. Pharm. Pharmacol. 49:669-674, 1997). Bothtransdermal and intradermal routes afford constant delivery for weeks ormonths.

The compounds can be provided as a salt and can be formed with manyacids, including but not limited to hydrochloric, sulfuric, acetic,lactic, tartaric, malic, succinic, etc. Salts tend to be more soluble inaqueous or other protonic solvents that are the corresponding free baseforms. In other cases, the preparation may be a lyophilized powder in 1mM-50 mM histidine, 0.1%-2% sucrose, 2%-7% mannitol at a pH range of 4.5to 5.5, that is combined with buffer prior to use

In another embodiment, the compounds are useful for parenteraladministration, such as intravenous (IV) administration oradministration into a body cavity or lumen of an organ. The formulationsfor administration will commonly comprise a solution of the compounddissolved in a pharmaceutically acceptable carrier. Among the acceptablevehicles and solvents that can be employed are water and Ringer'ssolution, an isotonic sodium chloride. In addition, sterile fixed oilscan conventionally be employed as a solvent or suspending medium. Forthis purpose any bland fixed oil can be employed including syntheticmono- or diglycerides. In addition, fatty acids such as oleic acid canlikewise be used in the preparation of injectables. These solutions aresterile and generally free of undesirable matter. These formulations maybe sterilized by conventional, well known sterilization techniques. Theformulations may contain pharmaceutically acceptable auxiliarysubstances as required to approximate physiological conditions such aspH adjusting and buffering agents, toxicity adjusting agents, e.g.,sodium acetate, sodium chloride, potassium chloride, calcium chloride,sodium lactate and the like. The concentration of the compound in theseformulations can vary widely, and will be selected primarily based onfluid volumes, viscosities, body weight, and the like, in accordancewith the particular mode of administration selected and the patient'sneeds. For IV administration, the formulation can be a sterileinjectable preparation, such as a sterile injectable aqueous oroleaginous suspension. This suspension can be formulated according tothe known art using those suitable dispersing or wetting agents andsuspending agents. The sterile injectable preparation can also be asterile injectable solution or suspension in a nontoxicparenterally-acceptable diluent or solvent, such as a solution of1,3-butanediol.

In another embodiment, the compound can be delivered by the use ofliposomes which fuse with the cellular membrane or are endocytosed,i.e., by employing ligands attached to the liposome, or attacheddirectly to the oligonucleotide, that bind to surface membrane proteinreceptors of the cell resulting in endocytosis. By using liposomes,particularly where the liposome surface carries ligands specific fortarget cells, or are otherwise preferentially directed to a specificorgan, one can focus the delivery of the compound into the target cellsin vivo. (See, e.g., Al-Muhammed, J. Microencapsul. 13:293-306, 1996;Chonn, Curr. Opin. Biotechnol. 6:698-708, 1995; Ostro, Am. J. Hosp.Pharm. 46:1576-1587, 1989).

The pharmaceutical preparation is preferably in unit dosage form. Insuch form the preparation is subdivided into unit doses containingappropriate quantities of the active component. The unit dosage form canbe a packaged preparation, the package containing discrete quantities ofpreparation, such as packeted tablets, capsules, and powders in vials orampoules. Also, the unit dosage form can be a capsule, tablet, cachet,or lozenge itself, or it can be the appropriate number of any of thesein packaged form.

The quantity of active component in a unit dose preparation may bevaried or adjusted from 0.1 mg to 10000 mg, more typically 1.0 mg to1000 mg, most typically 10 mg to 500 mg, according to the particularapplication and the potency of the active component. The compositioncan, if desired, also contain other compatible therapeutic agents.

Compounds of the invention may be metabolized by cells by phosphatasesof the phospholipase C type and then converted by anabolicphosphorylation sequentially to the acyclic nucleoside phosphonatemonophosphate (ANPp) and then to the acyclic nucleoside phosphonatediphosphate, (ANPpp), the active antiviral. For example ODE-(S)-MPMPA ismetabolized intracellularly in mammalian cells as shown in Scheme Afollowing, wherein “a” is a phosphatase of the phospholipase orlysophospholipase C type; “b” is a nucleoside monophosphate kinase, and“c” is a nucleoside diphosphate kinase. ODE-(S)-MPMPA, (S)-MPMPAp and(S)-MPMPApp are unique chemical entities and are compounds describedherein.

B. Effective Dosages

Pharmaceutical compositions provided herein include compositions whereinthe active ingredient is contained in a therapeutically effectiveamount, i.e., in an amount effective to achieve its intended purpose.The actual amount effective for a particular application will depend,inter alia, on the condition being treated. For example, whenadministered in methods to treat virus infection, such compositions willcontain an amount of active ingredient effective to achieve the desiredresult (e.g. decreasing the viral titer).

The dosage and frequency (single or multiple doses) of compoundadministered can vary depending upon a variety of factors, includingroute of administration; size, age, sex, health, body weight, body massindex, and diet of the recipient; nature and extent of symptoms of thedisease being treated; presence of other diseases or otherhealth-related problems; kind of concurrent treatment; and complicationsfrom any disease or treatment regimen. Other therapeutic regimens oragents can be used in conjunction with the methods and compoundsdescribed herein.

For any compound described herein, the therapeutically effective amountcan be initially determined from cell culture assays. Targetconcentrations will be those concentrations of active compound(s) thatare capable of decreasing viral activity as measured, for example, usingthe methods described.

Therapeutically effective amounts for use in humans may be determinedfrom animal models. For example, a dose for humans can be formulated toachieve a concentration that has been found to be effective in animals.The dosage in humans can be adjusted by monitoring viral inhibition andadjusting the dosage upwards or downwards, as described above.

Dosages may be varied depending upon the requirements of the patient andthe compound being employed. The dose administered to a patient, in thecontext of the present invention, should be sufficient to affect abeneficial therapeutic response in the patient over time. The size ofthe dose also will be determined by the existence, nature, and extent ofany adverse side effects. Generally, treatment is initiated with smallerdosages, which are less than the optimum dose of the compound.Thereafter, the dosage is increased by small increments until theoptimum effect under circumstances is reached. In one embodiment of theinvention, the dosage range is 0.001% to 10% w/v. In another embodiment,the dosage range is 0.1% to 5% w/v.

Dosage amounts and intervals can be adjusted individually to providelevels of the administered compound effective for the particularclinical indication being treated. This will provide a therapeuticregimen that is commensurate with the severity of the individual'sdisease state.

Utilizing the teachings provided herein, an effective prophylactic ortherapeutic treatment regimen can be planned that does not causesubstantial toxicity and yet is entirely effective to treat the clinicalsymptoms demonstrated by the particular patient. This planning shouldinvolve the careful choice of active compound by considering factorssuch as compound potency, relative bioavailability, patient body weight,presence and severity of adverse side effects, preferred mode ofadministration, and the toxicity profile of the selected agent.

C. Toxicity

The ratio between toxicity and therapeutic effect for a particularcompound is its therapeutic index and can be expressed as the ratiobetween LD₅₀ (the amount of compound lethal in 50% of the population)and ED₅₀ (the amount of compound effective in 50% of the population).Compounds that exhibit high therapeutic indices are preferred.Therapeutic index data obtained from cell culture assays and/or animalstudies can be used in formulating a range of dosages for use in humans.The dosage of such compounds preferably lies within a range of plasmaconcentrations that include the ED₅₀ with little or no toxicity. Thedosage may vary within this range depending upon the dosage formemployed and the route of administration utilized. See, e.g. Fingl etal., In: THE PHARMACOLOGICAL BASIS OF THERAPEUTICS, Ch. 1, p. 1, 1975.The exact formulation, route of administration, and dosage can be chosenby the individual physician in view of the patient's condition and theparticular method in which the compound is used.

VI. Examples

The examples below are meant to illustrate certain embodiments of theinvention, and not to limit the scope of the invention. Abbreviations:(S)-HPMPA, 9-(S)-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine;(S)-MPMPA, 9-(S)-[3-methoxy-2-(phosphonomethoxy)propyl]adenine; ODE,octadecyloxyethyl; HDP, hexadecyloxypropyl; ODE-(S)-MPMPA,octadecyloxyethyl 9-(S)-[3-methoxy-2-(phosphonomethoxy) propyl]adenine;ODE-(R)-MPMPA, octadecyloxyethyl9-(R)-[3-methoxy-2-(phosphonomethoxy)propyl]adenine; HDP-(S)-MPMPA,hexadecyloxypropyl 9-(S)-[3-methoxy-2-(phosphonomethoxy)propyl]adenine;HDP-(R,S)-EPMPA, hexadecyloxypropyl9-(R,S)-[3-ethoxy-2-(phosphonomethoxy)propyl]adenine; HDP-(R,S)-IPPMPA,hexadecyloxypropyl9-(R,S)-[3-isopropoxy-2-(phosphonomethoxy)propyl]adenine;ODE-(S)-MPMPDAP, octadecyloxyethyl9-(S)-[3-methoxy-2-(phosphonomethoxy)propyl]2,6-diaminopurine;HDP-(R,S)-EPMPDAP, hexadecyloxypropyl9-(R,S)-[3-ethoxy-2-(phosphonmethoxy)propyl]2,6-diaminopurine;ODE-(S)-MPMPG, octadecyloxyethyl9-(S)-[3-methoxy-2(phosphonomethoxy)propyl]guanine; ODE-(S)-MPMPC,octadecyloxyethyl 1-(S)-[3-methoxy-2-(phosphonmethoxy)propyl]cytosine;HDP-(S)-MPMPMP, hexadecyloxypropyl9-(S)-[3-methoxy-2-(phosphonomethoxy)propyl]6-methoxypurine;HDP-(S)-MPMPOMG, hexadecyloxypropyl9-(S)-[3-methoxy-2-(phosphonomethoxy) propyl]6-O-methylguanine.

General.

All reagents were of commercial quality and used without furtherpurification unless indicated otherwise. Chromatographic purificationwas done using the flash method with silica gel 60 (EMD Chemicals, Inc.,230-400 mesh). ¹H NMR spectra were recorded on Varian HGspectrophotometers operating at 400 MHz and are reported in units ofparts per million (ppm) relative to internal tetramethylsilane at 0.00ppm. Assignments of ¹H NMR signals are made using the numbering systemshown in Scheme B following.

Scheme B. Numbering System for NMR Signal Assignment

Routine electrospray ionization mass spectra (ESI-MS) were recorded on aFinnigan LCQDECA spectrometer, and high resolution mass spectra (HRMS)on an Agilent 6230 Accurate-Mass TOFMS mass spectrometer in ESI negativemode. Purity of the target compounds was characterized by highperformance liquid chromatography (HPLC) using a Beckman Coulter SystemGold chromatography system. The analytical column was PhenomenexSynergi™ Polar-RP (4.6×150 mm) equipped with a SecurityGuard™ protectioncolumn. Mobile phase A was 95% water/5% methanol and mobile phase B was95% methanol/5% water. At a flow rate of 0.8 mL/min, gradient elutionwas as follows: 10% B (0-3 min.); 10% to 95% B (3-20 min.); 95% B (20-25min.); 95% to 10% B (25-34 min.). Compounds were detected by ultravioletlight (UV) absorption at 274 nm. Purity of compounds was also assessedby thin layer chromatography (TLC) using Analtech silica gel-GF (250 m)plates and the solvent system: CHCl₃/MeOH/con NH₄OH/H₂O (70:30:3:3 v/v).TLC results were visualized with UV light, phospray (Supelco,Bellefonte, Pa., USA) and charring at 400° C. The key synthons,hexadecyloxypropyl- and octadecyloxyethylp-toluenesulfonyloxymethylphosphonate, were prepared as describedpreviously. See e.g., Beadle, et al., 2006, Id.

Compounds.

Compound numbering as used herein is provided in Table 4 following whichsets forth substituents B^(N), R¹ and R² of Formula (I), structure, andcommon name abbreviation.

TABLE 4 Cmpd B^(N) R¹ R² Structure, name 1 adenine H ODE

15 Me ODE

16 Me ODE

17 Me HDP

18 ethyl HDP

19 isopropyl HDP

23 2,6- diamino- purine Me ODE

24 Me ODE

25 Me HDP

26 ethyl HDP

34 guanine Me ODE

35 Me ODE

36 Me HDP

37 ethyl HDP

40 cytosine Me ODE

43 6- methoxy- purine Me HDP

44 6-O- methyl- guanine Me HDP

Example 1—General Procedure A. Synthesis of 3-Alkoxy-2-HydroxypropylNucleoside Analogs

The preparation of 3-alkoxy-2-hydroxypropyl nucleoside analogs wasaccomplished using the base catalyzed ring-opening reaction of alkylglycidyl ethers with nucleobases as described by Brodfuehrer et al. SeeBrodfuehrer, P. R., et al., 1994, Tetrahedron Lett. 35:3243-3246. Sodiumhydride (2 mmol) was added to a solution of the nucleic acid base (10mmol) and an alkyl glycidyl ether (10 mmol) in anhydrousN,N-dimethylformamide (50 mL) and the mixture was stirred and heated to100° C. for 6 hours. After cooling, the reaction was quenched with H₂O,the solvent was removed in vacuo and the residue was purified by flashcolumn chromatography on silica gel. Elution of the column with 10%MeOH/CH₂Cl₂ gave the product.

With reference to Scheme 1 following, reagents were the following: a)NaH, alkyl glycidyl ether, N,N-DMF, 100° C., 6 h; b)bromotrimethylsilane, monomethoxytrityl chloride, pyridine; c) sodiumt-butoxide, hexadecyloxypropyl (HDP) or octadecyloxyethyl (ODE)p-toluenesulfonyloxymethylphosphonate, N,N-DMF, 80° C., 16 h; d) 80% aqacetic acid, 60° C., 2 h.

Example 2—(S)-9-[(3-methoxy-2-hydroxy)propyl]adenine (2)

(S)-9-[(3-methoxy-2-hydroxy)propyl]adenine (2) was synthesized fromadenine and (S)-methyl glycidyl ether (TCI America, Portland, Oreg.).75% yield. ¹H NMR (CDCl₃/methanol-d₄) δ 8.25 (s, 1H); 8.03 (s, 1H);4.39-4.44 (m, 1H); 4.19-4-25 (m, 1H); 4.08-4.18 (m, 1H); 3.37-3.44 (m,2H); 3.40 (s, 3H). MS (ESI): 224.14 [M+H]⁺.

Example 3—(R)-9-[(3-methoxy-2-hydroxy)propyl]adenine (3)

(R)-9-[(3-methoxy-2-hydroxy)propyl]adenine (3) was synthesized fromadenine and (R)-methyl glycidyl ether (TCI America, Portland, Oreg.).72% yield. ¹H NMR (methanol-d₄) δ 8.20 (s, 1H, H-8); 8.08 (s, 1H, H-2);4.39 (dd, 1H, H-1′a, J_(1′a,2′)=3.4 Hz, J_(gem)=14.2 Hz); 4.20 (dd, 1H,H-1′b, J_(1′b,2′)=8.0 Hz, J_(gem)=14.2 Hz); 4.11 (m, 1H, H-2′); 3.42 (d,2H, H-3′, J_(3′,2)′=5.2 Hz); 3.37 (s, 3H, —OCH₃).

Example 4—(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]adenine (4)

(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]adenine (4) was synthesized fromadenine and (R,S)-ethyl glycidyl ether (TCI America) with 59% yield. ¹HNMR (CDCl₃/methanol-d₄), δ:8.24 (s, 1H); 8.04 (s, 1H); 4.40-4.65 (m,1H); 4.20-4-27 (m, 1H); 4.10-4.15 (m, 1H); 3.55-3.57 (m, 2H); 3.46-3.54(m, 2H); 1.21 (t, J=7 Hz, 3H). MS (ESI): 238.09 [M+H]⁺.

Example 5—(R,S)-9-[(3-isopropoxy-2-hydroxy)propyl]adenine (5)

(R,S)-9-[(3-isopropoxy-2-hydroxy)propyl]adenine (5) was synthesized fromadenine and (R,S) isopropyl glycidyl ether (Aldrich Chem.). 33.8% yield.¹H NMR (CDCl₃/methanol-d₄), δ 8.21 (s, 1H, H-8); 8.08 (s, 1H, H-2); 4.41(dd, 1H, H-1′a, J_(1′a,2′)=3.8, J_(gem)=14.2 Hz); 4.23 (dd, 1H, H-1′b,J_(1′,2′)=7.6 Hz, J_(gem)=14.4 Hz); 4.10 (m, 1H, H-2′); 3.60 (septet,1H, —CH(CH₃)₂, J=6.0 Hz); 1.16 (d, 6H, —CH(CH₃)₂).

Example 6—General procedure B. Synthesis of9-[(3-alkoxy-2-hydroxy)propyl]-N6-monomethoxytrityladenine (6-9)

The monomethoxytrityl group was used to block the exocylic amino groupof adenine and was introduced by the transient protection methoddescribed by Ti et al.³ Bromotrimethylsilane (6.3 mmol) was addeddropwise to a suspension of 9-[(2-hydroxy-3-alkoxy)propyl]adenine (2-5)(2.8 mmol) in dry pyridine (10 mL). The mixture was stirred 15 min.until it became clear, then monomethoxytrityl chloride (0.99 g, 3.2mmol) and 4-(dimethylamino)pyridine (20 mg, 0.2 mmol) were added andstirring was continued overnight. The mixture was cooled with an icebath and H₂O (1 mL) was added. Stirring was continued 10 min., then con.NH₄OH (1 mL) was added and the reaction was stirred 30 additional min.The mixture was allowed to warm to room temperature and filtered througha pad of Celite®. The filtrate was evaporated in vacuo and the residuewas purified by flash column chromatography on silica gel. Gradientelution (100% hexanes to 100% ethyl acetate) afforded theN⁶-monomethoxytrityl 9-[(2-alkoxy-3-methoxy)propyl]adenines (6-9).

Example7—(S)-9-[(3-methoxy-2-hydroxy)propyl]-N6-monomethoxytrityladenine (6)

(S)-9-[(3-methoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine (6) wassynthesized from 2. 98% yield. ¹H NMR (CDCl₃/methanol-d₄), δ 8.17 (s,1H, H-8); 8.13 (s, 1H, H-2); 7.39-7.75 (m, 14H, trityl); 4.50-4.59 (m,1H); 4.31-4.39 (m, 1H); 4.22-4.30 (m, 1H); 3.45 (s, 3H); 3.50-3.60 (m,2H); 3.55 (s, 3H). MS (ESI): 496.06 [M+H]⁺, 518.13 [M+Na]⁺.

Example 8—(R)-9-[(3-methoxy-2-hydroxy)propyl]N6-monomethoxytrityladenine (7)

(R)-9-[(3-methoxy-2-hydroxy)propyl] N⁶-monomethoxytrityladenine (7) wassynthesized from Cmpd 3. 19% yield. ¹H NMR (CDCl₃/methanol-d₄), δ 8.03(s, 1H, H-8); 7.78 (s, 1H, H-2); 7.35-7.33 (m, 4H, trityl); 7.29-7.24(m, 10H, trityl); 4.61 (d, 1H, H-1′a, J_(1′a,2′)=4 Hz); 4.39 (dd, 1H,H-1′b, J_(1′,b,2′)=2.2 Hz, J_(gem)=13.8 Hz); 4.16 (m, 1H, H-2′); 3.78(s, 3H, Ar—OCH₃); 3.41 (dd, 1H, H-3′a, J_(3′a,2′)=5.2 Hz, J_(gem)=9.2Hz); 3.36 (s, 3H, CH₂—OCH₃); 3.33 (dd, 1H, H-3′b, J_(3′b,2′)=6.2 Hz,J_(gem)=9.8 Hz).

Example 9—(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]N6-monomethoxytrityladenine (8)

(R,S)-9-[(3-ethoxy-2-hydroxy)propyl] N⁶-monomethoxytrityladenine (8) wassynthesized from 4. 78% yield. ¹H NMR (CDCl₃/methanol-d₄), δ 7.98 (s,1H); 7.25-7.34 (m, 14H); 6.82 (s, 1H); 4.35-4.43 (m, 1H); 4.15-4.24 (m,1H); 4.05-4.15 (m, 1H); 3.78 (s, 3H); 3.52-3.56 (m, 2H); 3.44-3.47 (m,2H); 1.20 (t, J=7 Hz, 3H). MS (ESI): 509.78 [M+H]⁺.

Example 10—(R,S)-9-[(3-isopropoxy-2-hydroxy)propyl]N6-monomethoxytrityladenine (9)

(R,S)-9-[(3-isopropoxy-2-hydroxy)propyl] N⁶-monomethoxytrityl adenine(9) was synthesized from Cmpd 5. 32% yield. ¹H NMR (DMSO-d₆) δ 8.10 (s,1H, H-8); 7.89 (s, 1H, H-2); 7.28-7.26 (m, 10H, trityl); 7.21-7.18 (m,4H, trityl); 6.83 (d, 1H, —NH—); 5.16 (d, 1H, —OH); 4.23 (dd, 1H, H-1′a,J_(1′a,2′)=3.4 Hz, J_(gem)=13.8 Hz); 3.98 (dd, 1H, H-1′b, J_(1′b,2′)=8.4Hz, J_(gem)=13.6 Hz); 3.92 (m, 1H, H-2′); 3.70 (s, 3H, Ar—OCH₃); 3.50(septet, 1H, —CH(CH₃)₂); 3.35 (dd, 1H, J_(3′a,2′)=4.8 Hz, J_(gem)=10Hz); 3.27 (dd, 1H, H-3′b, J_(3b,2′)=6, J_(gem)=9.6); 1.04 (dd, 6H,—CH(CH₃)₂).

Example 11—General procedure C. Alkylation of9-[(3-alkoxy-2-hydroxy)propyl] derivatives (6-9, 20-22, 27-29, 38,41-42) with alkoxyalkyl p-toluenesulfonyloxymethylphosphonate. Synthesisof (10-14, 23-26, 30-33, 39, 43-44)

Sodium t-butoxide (0.19 g, 2.0 mmol) was added to a solution of the3-alkoxy-2-hydroxypropyl nucleoside (1.0 mmol) and the alkoxyalkylp-toluenesulfonyloxymethylphosphonate¹ (2.0 mmol) in anhydrous N,N-DMF(20 mL). The mixture was heated to 80° C. and kept overnight. Aftercooling, the solvents were evaporated in vacuo and the residue waspurified by flash column chromatography on silica gel. The column waseluted with a gradient: chloroform 100%-chloroform-methanol (20%) togive the products.

Example 12—Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]N6-monomethoxytrityladenine, sodium salt (10)

Octadecyloxyethyl (S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]N⁶-monomethoxytrityladenine, sodium salt (10) was synthesized from(S)-9-[(3-methoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine (6) andoctadecyloxyethyl p-toluenesulfonyloxymethylphosphonate. 60% yield. ¹HNMR (CDCl₃/methanol-d₄), δ 8.18 (s, 1H); 7.98 (s, 1H); 7.22-7.55 (m,14H); 4.38-4.50 (m, 2H); 4.12-4.37 (m, 2H); 4.00-4.08 (m, 1H); 3.82-3.98(m, 2H); 3.79 (s, 3H); 3.58-3.65 (m, 2H); 3.44-3.48 (m, 2H); 3.38-3.43(m, 2H); 3.35 (s, 3H); 1.40-1.60 (m, 2H); 1.16-1.38 (m, 30H); 0.88 (t,J=7 Hz, 3H). MS (ESI): 886.48 [M+H]⁺.

Example 13—Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]N6-monomethoxytrityladenine, sodium salt (11)

Octadecyloxyethyl (R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]N⁶-monomethoxytrityladenine, sodium salt (11) was synthesized from(R)-9-[(3-methoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine (7) andoctadecyloxyethyl p-toluenesulfonyloxymethylphosphonate. 43% yield. ¹HNMR (CDCl₃/methanol-d₄), δ 8.20 (s, 1H); 7.98 (s, 1H); 7.22-7.37 (m,14H); 4.42-4.50 (m, 1H); 4.28-4.37 (m, 1H); 3.91-3.98 (m, 2H); 3.82-3.90(m, 2H); 3.79 (s, 3H); 3.60-3.69 (m, 1H); 3.48-3.58 (m, 3H); 3.39-3.46(m, 2H); 3.35 (s, 3H); 1.45-1.60 (m, 2H); 1.20-1.38 (m, 30H); 0.88 (t,J=7 Hz, 3H). MS (ESI): 886.57 [M+H]⁺.

Example 14—Hexadecyloxypropyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]N6-monomethoxytrityladenine, sodium salt (12)

Hexadecyloxypropyl (S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]N⁶-monomethoxytrityladenine, sodium salt (12) was synthesized from(S)-9-[(3-methoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine (6) andhexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate. 77% yield. ¹HNMR (CDCl₃/methanol-d₄), δ: 8.17 (s, 1H); 7.94 (s, 1H); 7.22-7.36 (m,14H); 4.38-4.50 (m, 2H); 4.28-4.37 (m, 2H); 3.82-3.98 (m, 2H); 3.79 (s,3H); 3.58-3.65 (m, 1H); 3.38-3.58 (m, 6H); 3.34 (s, 3H); 1.78-1.87 (m,2H); 1.44-1.60 (m, 2H); 1.10-1.40 (m, 26H); 0.88 (t, J=7 Hz, 3H). MS(ESI): 870.33 [M−H]⁻.

Example 15—Hexadecyloxypropyl(R,S)-9-[(3-ethoxy-2-phosphonomethoxy)propyl]N6-monomethoxytrityladenine, sodium salt (13)

Hexadecyloxypropyl (R,S)-9-[(3-ethoxy-2-phosphonomethoxy)propyl]N⁶-monomethoxytrityladenine, sodium salt (13) was synthesized from(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine (8) andhexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate. 80% yield. ¹HNMR (CDCl₃/methanol-d₄), δ: 8.19 (s, 1H); 7.98 (s, 1H); 7.20-7.36 (m,14H); 4.42-4.65 (m, 1H); 4.28-4.37 (m, 1H); 3.80-3.95 (m, 3H); 3.78 (s,3H); 3.48-3.65 (m, 6H); 3.28-3.48 (m, 2H); 1.78-1.87 (m, 2H); 1.44-1.55(m, 2H); 1.08-1.30 (m, 26H); 1.15 (t, J=7 Hz, 3H); 0.88 (t, J=7 Hz, 3H).MS (EI): 886.42 (M+H)⁺.

Example 16—Hexadecyloxypropyl(R,S)-9-[(3-isopropoxy-2-phosphonomethoxy)propyl]N6-monomethoxytrityladenine, sodium salt (13)

Hexadecyloxypropyl (R,S)-9-[(3-isopropoxy-2-phosphonomethoxy)propyl]N⁶⁻monomethoxytrityladenine, sodium salt (13) was synthesized from(R,S)-9-[(3-isopropoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine (9)and hexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate. 25% yield.¹H NMR (CDCl₃/methanol-d₄) δ 8.15 (s, 1H, H-8); 7.88 (s, 1H, H-2);7.30-7.25 (m, 4H, trityl); 7.20-7.12 (m, 10H, trityl); 4.66 (dd, 1H,H-1′a, J_(1′a,2′)=3.5 Hz, J_(gem)=14.2 Hz); 4.47 (dd, 1H, H-1′b,J_(1′b2′)=6.2 Hz, J_(gem)=14.0 Hz); 4.01 (m, 2H, —P—O—CH₂—); 3.88 (dd,1H, —CH_(a)—P—, J_(P,CHa)=9.2 Hz, J_(gem)=13.6 Hz); 3.71 (dd, 1H,—CH_(b)—P—, J_(P,CHb)=9.6 Hz, J_(gem)=14.0 Hz); 3.75-3.55 (m, 3H,H-3′+H-2′); 3.51 (t, 2H, —CH—O—CH₂—); 3.45 (t, 2H, —CH₂—O—CH₂—); 1.83(pentet, 2H, —O—CH₂CH₂CH₂O—); 1.53 (m, 2H, —CH₂(CH₂)₁₅—); 1.27 (m, 26H,—(CH₂)₁₅—); 1.10 (d, 6H, —CH(CH₃)₂); 0.89 (t, 3H, —CH₃).

Example 17—General procedure D. Synthesis ofAlkoxyalkyl-9-[(3-alkoxy-2-phosphonomethoxy)propyl]adenine (15-19)

Alkoxyalkyl 9-[(3-alkoxy-2-hydroxy)propyl]-N⁶-monomethoxytrityladenine(10-14) (0.60 mmol) was added to 80% acetic acid, stirred and heated to60° C. for 2 hours. After cooling, the solvent was removed in vacuo andthe residue purified by flash column chromatography on silica gel.Elution with 20% MeOH/CH₂Cl₂ gave the products.

Example 18—Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]adenine, sodium salt(ODE-(S)-MPMPA) (15)

Octadecyloxyethyl (S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]adenine,sodium salt (ODE-(S)-MPMPA) (15). Deprotection of Cmpd 10 (procedure D)gave Cmpd 15 in 73% yield as a white powder. ¹H NMR (CDCl₃/methanol-d₄)δ 8.35 (s, 1H, H-8); 8.22 (s, 1H, H-2); 4.53 (dd, H, H-1′a,J_(1′a2′)=3.3 Hz, J_(gem) 14.3 Hz); 4.37 (dd, 1H, H-1′b, J_(1′b2′)=6.6Hz, J_(gem) 14.7 Hz); 4.01-3.98 (m, 3H, P—O—CH₂—+H-2′); 3.87 (dd, 1H,—CH_(a)—P—, J_(P,CHa)=9.2 Hz, J_(gem)=13.2); 3.70 (dd, 1H, —CH_(b)—P—,J_(P,CHb)=9.0 Hz, J_(gem)=13.0 Hz); 3.57 (t, 2H, —CH₂—O—); 3.44 (t, 2H,—O—CH₂—); 1.53 (m, 2H, —O—CH₂CH₂(CH₂)₁₅—); 1.26 (m, 30H, —(CH₂)₁₅CH₃);0.89 (t, 3H, —CH₃, J=7 Hz). MS (ESI+): 614.41 [M+H]⁺; HRMS (ESI−) calcd.for C₃₀H₅₅N₅O₆P [M−H]⁻ 612.3895. found 612.3897 (E=0.3 ppm). HPLCanalysis: retention time 22.35 min., purity 96.12%.

Example 19—Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]adenine, sodium salt(ODE-(R)-MPMPA) (16)

Octadecyloxyethyl (R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]adenine,sodium salt (ODE-(R)-MPMPA) (16). Deprotection of 11 gave 16 in 72%yield. ¹H NMR (CDCl₃/methanol-d₄), δ: 8.24 (s, 1H); 8.21 (s, 1H);4.43-4.54 (s, 1H); 4.25-4.35 (m, 1H); 3.88-3.98 (m, 3H); 3.80-3.88 (m,1H); 3.50-3.60 (m, 4H); 3.38-3.48 (m, 3H); 3.37 (s, 3H); 1.49-1.56 (m,2H); 1.20-1.35 (m, 30H); 0.88 (t, J=7 Hz, 3H). MS (ESI+): 614.55 [M+H]⁺,636.46 [M+Na]⁺. HRMS (ESI−) calcd. for C₃₀H₅₅N₅O₆P [M−H]⁻ 612.3895.found 612.3900 (E=0.8 ppm). HPLC analysis: retention time 21.82 min.,purity 95.24%.

Example 20—Hexadecyloxypropyl(S)-9-[3-methoxy-2-phosphonomethoxy)propyl]adenine, sodium salt(HDP-(S)-MPMPA) (17)

Hexadecyloxypropyl (S)-9-[3-methoxy-2-phosphonomethoxy)propyl]adenine,sodium salt (HDP-(S)-MPMPA) (17). Deprotection of 12 gave 17 in 77%yield. ¹H NMR (CDCl₃/methanol-d₄), δ 8.28 (s, 1H); 8.23 (s, 1H);4.48-4.61 (s, 2H); 4.32-4.37 (m, 2H); 3.91-3.96 (m, 2H); 3.80-3.86 (m,1H); 3.58-3.64 (m, 1H); 3.41-3.57 (m, 3H); 3.30-3.41 (m, 2H); 3.38 (s,3H); 1.82-1.90 (m, 2H); 1.49-1.55 (m, 2H); 1.18-1.38 (m, 26H); 0.89 (t,J=7 Hz, 3H). MS (ESI−): 598.29 [M−H]—. HRMS (ESI−) calcd. forC₂₉H₅₃N₅O₆P [M−H]⁻ 598.3739. found 598.3737 (E=−0.3 ppm). HPLC analysis:retention time 22.43 min., purity 93.0%.

Example 21—Hexadecyloxyethyl(R,S)-9-[(3-ethoxy-2-phosphonomethoxy)propyl]adenine, sodium salt(HDP-(R,S)-EPMPA) (18)

Hexadecyloxyethyl (R,S)-9-[(3-ethoxy-2-phosphonomethoxy)propyl]adenine,sodium salt (HDP-(R,S)-EPMPA) (18). Deprotection of 13 gave 18 in 92%yield. ¹H NMR (CDCl₃/methanol-d₄), δ 8.28 (s, 1H); 8.21 (s, 1H);4.48-4.53 (s, 1H); 4.34-4.39 (m, 1H); 3.90-4.00 (m, 3H); 3.80-3.86 (m,1H); 3.58-3.64 (m, 1H); 3.44-3.58 (m, 6H); 3.35-3.41 (m, 2H); 1.82-1.90(m, 2H); 1.49-1.58 (m, 2H); 1.22-1.38 (m, 26H); 1.20 (t, J=7 Hz, 3H);0.89 (t, J=7 Hz, 3H). MS (ESI): 612.44 (M−H)⁻. HRMS (ESI−) calcd. forC₃₀H₅₅N₅O₆P [M−H]⁻ 612.3895. found 612.3898 (E=0.5 ppm). HPLC analysis:retention time 22.60 min., purity 91.8%

Example 22—Hexadecyloxyethyl(S)-9-[(3-isopropoxy-2-phosphonomethoxy)propyl]adenine, sodium salt(HDP-(R,S)-IPPMPA) (19)

Hexadecyloxyethyl (S)-9-[(3-isopropoxy-2-phosphonomethoxy)propyl]adenine, sodium salt (HDP-(R,S)-IPPMPA) (19). Deprotection of 14 gave 19in 75% yield. ¹H NMR (methanol-d₄) δ 8.35 (s, 1H, H-8), 8.25 (s, 1H,H-2), 4.53, (dd, 1H, H-1′a, J_(1′a2′)=3.4 Hz, J_(gem)=14.6 Hz), 4.39(dd, 1H, H-1′b, J_(1′b2′)=6.6 Hz, J_(gem)=14.6 Hz), 3.93 (t, 2H,P—O—CH_(a), J=6.8 Hz), 3.91 (t, 1H, P—O—CH_(b), J=6.4 Hz); 3.85 (dd,—CH_(a)—P—, J_(P,CHa)=9.0 Hz, J_(gem)=13 Hz), 3.66 (dd, 1H, —CH_(b)—P—,J_(P,Hb)=9.6 Hz, J_(gem)=13.2 Hz); 3.59-3.48 (m, 3H, H-3′+H-2′), 3.46(t, 2H, —CH₂—O—CH₂), 3.37 (t, 2H, —CH₂—O—CH₂—), 1.80 (pentet, 2H,—O—CH₂—CH₂—CH₂—O—), 1.51 (m, 2H, —O—CH₂—CH₂—(CH₂)₁₃—), 1.27 (m, 26H,—(CH₂)₁₃—), 1.13 (d, 6H, —CH(CH₃)₂), 0.89 (t, 3H, —CH₃); MS (ESI−):626.69 [M−H]⁻. HRMS (ESI−) calcd. for C₃₁H₅₇N₅O₆P [M−H]⁻ 626.4052. found626.4053 (E=0.2 ppm). HPLC analysis: retention time 21.95 min., purity97.1%.

Example 23—Diaminopurine Derivatives (23-26)

A scheme useful for synthesis of diaminopurine compounds describedherein is provided in Scheme 2 following, with reagents and conditionsas following: a) NaH, alkyl glycidyl ether, N,N-DMF, 100° C., 6H; b)sodium t-butoxide, alkoxyalkyl p-toluenesulfonyloxymethylphosphonate,N,N-DMF, 80° C.

Example 24—(S)-9-[(3-methoxy-2-hydroxy)propyl]-2, 6-diaminopurine (20)

(S)-9-[(3-methoxy-2-hydroxy)propyl]-2,6-diaminopurine (20) wassynthesized from 2,6-diaminopurine (TCI America) and (S)-methyl glycidylether (procedure A). 27% yield (0.65 g). ¹H NMR (CDCl₃/methanol-d₄), δ7.68 (s, 1H, H-8); 4.20-4.30 (m, 1H); 4.05-4.12 (m, 2H); 3.32-3.47 (m,2H); 3.39 (s, 3H).

Example 25—(R)-9-[(3-methoxy-2-hydroxy)propyl]-2, 6-diaminopurine (21)

(R)-9-[(3-methoxy-2-hydroxy)propyl]-2,6-diaminopurine (21) wassynthesized from 2,6-diaminopurine and (R)-methyl glycidyl ether(procedure A). 41% yield. ¹H NMR (CDCl₃/methanol-d₄), δ 7.73 (s, 1H,H-8); 4.22 (d, 1H, H-1′a, J_(gem)=12.4 Hz), 4.06-4.02 (m, 2H,H-1′b+H-2′); 3.39 (d, 2H, H-3′, J=3.2 Hz); 3.36 (s, 3H, —OCH₃).

Example 26—(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]-2, 6-diaminopurine (22)

(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]-2,6-diaminopurine (22) wassynthesized from 2,6-diaminopurine and (R,S)-ethyl glycidyl ether(procedure A). 71% yield. ¹H NMR (CDCl₃/methanol-d₄) δ 7.77 (s, 1H,H-8); 4.22 (dd, 1H, J_(1′a,2′)=3.6 Hz, J_(gem)=12.4 Hz, H-1′a);4.06-4.02 (m, 2H, H-1′b+H-2′); 3.88 (q, 2H, —OCH₂CH₃); 3.39 (d, 2H,H-3′, J=3.2 Hz); 1.16 (t, 3H, —OCH₂CH₃).

Example 27—Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]2, 6-diaminopurine, sodiumsalt (ODE-(S)-MPMPDAP) (23)

Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]2,6-diaminopurine, sodiumsalt (ODE-(S)-MPMPDAP) (23) was synthesized (procedure C) from(S)-9-[(3-methoxy-2-hydroxy)propyl]2,6-diaminopurine andoctadecyloxyethyl p-toluenesulfonyloxymethylphosphonate. 50% yield. ¹HNMR (CDCl₃/methanol-d₄), δ 7.72 (s, 1H); 4.00-4.20 (m, 5H); 3.80-3.90(m, 1H); 3.58-3.65 (m, 2H); 3.50-3.58 (m, 2H); 3.40-3.50 (m, 1H); 3.44(s, 3H); 3.30-3.38 (m, 2H); 1.50-1.60 (m, 2H); 1.18-1.38 (m, 30H); 0.88(t, J=7 Hz, 3H). MS (ESI): 627.48 [M−H]—, 629.47 [M+H]⁺. HRMS (ESI−)calcd. for C₃₀H₅₆N₆O₆P [M−H]⁻ 627.4004. found 627.4007 (E=0.5 ppm). HPLCanalysis: retention time 23.67 min., purity 91.9%.

Example 28—Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]2, 6-diaminopurine, sodiumsalt (ODE-(R)-MPMPDAP) (24)

Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]2,6-diaminopurine, sodiumsalt (ODE-(R)-MPMPDAP) (24) was synthesized (procedure C) from(R)-9-[(3-methoxy-2-hydroxy)propyl]2,6-diaminopurine andoctadecyloxyethyl p-toluenesulfonyloxymethylphosphonate with 49% yield.¹H NMR (CDCl₃/methanol-d₄), δ: 7.75 (s, 1H); 4.42-4.51 (m, 1H);4.00-4.20 (m, 4H); 3.80-3.90 (m, 1H); 3.60-3.65 (m, 2H); 3.50-3.58 (m,2H); 3.40-3.50 (m, 1H) 3.49 (s, 3H); 3.30-3.38 (m, 2H); 1.50-1.62 (m,2H); 1.20-1.38 (m, 30H); 0.88 (t, J=7 Hz, 3H). MS (ESI+): 629.55 [M+H]⁺.HRMS (ESI−) calcd. for C₃₀H₅₆N₆O₆P [M−H]⁻ 627.4004. found 627.4007(E=0.5 ppm). HPLC analysis: retention time 23.67, purity 98.4%.

Example 29—Hexadecyloxypropyl(S)-9-[3-methoxy-2-phosphonomethoxy)propyl]-2, 6-diaminopurine, sodiumsalt (HDP-(S)-MPMPDAP) (25)

Hexadecyloxypropyl(S)-9-[3-methoxy-2-phosphonomethoxy)propyl]-2,6-diaminopurine, sodiumsalt (HDP-(S)-MPMPDAP) (25) was synthesized (procedure C) from(S)-9-[(3-methoxy-2-hydroxy)propyl]2,6-diaminopurine andhexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate with 30% yield.¹H NMR (CDCl₃/methanol-d₄), δ: 7.72 (s, 1H); 4.02-4.20 (m, 3H);3.95-4.02 (m, 2H); 3.78-3.85 (m, 2H); 3.45-3.60 (m, 3H); 3.38-3.45 (m,6H); 1.82-1.95 (m, 2H); 1.45-1.60 (m, 2H); 1.20-1.38 (m, 26H); 0.88 (t,J=7 Hz, 3H). MS (ESI+): 615.50 [M+H]⁺, 637.45 [M+Na]⁺. HRMS (ESI−)calcd. for C₂₉H₅₄N₆O₆P [M−H]⁻ 613.3848. found 613.3854 (E=1.0 ppm). HPLCanalysis: retention time 22.98 min., purity 90.3%.

Example 30—Hexadecyloxypropyl(R,S)-9-[3-ethoxy-2-phosphonomethoxy)propyl-2, 6-diaminopurine, sodiumsalt (HDP-(R,S)-EPMPDAP) (26)

Hexadecyloxypropyl(R,S)-9-[3-ethoxy-2-phosphonomethoxy)propyl-2,6-diaminopurine, sodiumsalt (HDP-(R,S)-EPMPDAP) (26) was synthesized (procedure C) from(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]2,6-diaminopurine andhexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate with 22% yield.¹H NMR (CDCl₃/methanol-d₄), δ: 7.40 (s, 1H); 4.44-4.52 (m, 1H);4.18-2.28 (m, 1H); 3.91-4.10 (m, 3H); 3.80-3.90 (m, 1H); 3.45-3.60 (m,5H); 3.38-3.45 (m, 4H); 1.82-1.95 (m, 2H); 1.45-1.60 (m, 2H); 1.15-1.38(m, 28H); 0.88 (t, J=7 Hz, 3H). MS (ESI−): 627.53 [M−H]⁻. HRMS (ESI−)calcd. for C₃₀H₅₆N₆O₆P [M−H]⁻ 627.4004, found 627.4008 (E=0.6 ppm). HPLCanalysis: retention time 23.37 min., purity 96.4%.

Example 31—GuanineDerivatives (34-37)

A scheme useful for synthesis of guanine containing compounds describedherein is provided in Scheme 3 following, with reagents and conditionsas following: a) NaH, alkyl glycidyl ether, N,N-DMF, 100° C., 6 h; b)sodium t-butoxide, hexadecyloxypropyl (HDP) or octadecyloxyethyl (ODE)p-toluenesulfonyloxymethylphosphonate, N,N-DMF, 80° C.; c) 10%CF₃COOH/CH₂Cl₂, rt, 2 days.

Example 32—(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine (27)

(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine (27) wassynthesized from 6-O-benzylguanine (APAC Pharmaceutical LLC, Columbia,Md.) and (S)-methyl glycidyl ether (procedure A). 49% yield. ¹H NMR(CDCl₃/methanol-d₄), δ 7.75 (s, 1H); 7.49-7.51 (m, 2H); 7.29-7.40 (m,3H); 5.55 (s, 2H); 4.23-4.32 (m, 1H); 4.05-4.14 (m, 2H); 3.39-3.41 (m,2H); 3.39 (s, 3H).

Example 33—(R)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine (28)

(R)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine (28) wassynthesized from 6-O-benzylguanine and (R)-methyl glycidyl ether(procedure A). 44% yield. ¹H NMR (CDCl₃/methanol-d₄), δ 7.74 (s, 1H);7.47-7.51 (m, 2H); 7.29-7.40 (m, 3H); 5.55 (s, 2H); 4.40-4.60 (m, 1H);4.05-4.14 (m, 2H); 3.32-3.45 (m, 2H); 3.39 (s, 3H).

Example 34-(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]-6-O-benzylguanine (29)

(R,S)-9-[(3-ethoxy-2-hydroxy)propyl]-6-O-benzylguanine (29) wassynthesized from 6-O-benzylguanine and (R,S) ethyl glycidyl ether(procedure A). 51% yield. ¹H NMR (CDCl₃/methanol-d₄), δ 7.76 (s, 1H);7.50-7.52 (m, 2H); 7.32-7.40 (m, 3H); 5.52 (s, 2H); 4.17-4.21 (m, 1H);3.95-4.00 (m, 2H); 3.44-3.50 (m, 2H); 3.34-3.38 (m, 2H); 1.16 (t, J=7Hz, 3H).

Example 35—Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (30)

Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (30) wassynthesized (procedure C) from(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine andoctadecyloxyethyl p-toluenesulfonyloxymethylphosphonate. 26% yield. ¹HNMR (CDCl₃/methanol-d₄), δ 7.93 (s, 1H); 7.50-7.56 (m, 2H); 7.31-7.40(m, 3H); 5.55 (s, 2H); 4.24-4.36 (m, 1H); 3.93-4.22 (m, 1H); 3.75-3.98(m, 4H); 3.60-3.70 (m, 4H); 3.30-3.60 (m, 8H); 1.42-1.60 (m, 2H);1.18-1.38 (m, 30H); 0.89 (t, J=7 Hz, 3H). MS (ESI): 720.51 [M+H]⁺.

Example 36—Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (31)

Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (31) wassynthesized (procedure C) from(R)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine andoctadecyloxyethyl p-toluenesulfonyloxymethylphosphonate. 83% yield. ¹HNMR (CDCl₃/methanol-d₄), δ 7.93 (s, 1H); 7.52-7.47 (m, 2H); 7.23-7.38(m, 3H); 5.55 (s, 2H); 4.18-4.38 (m, 2H); 3.75-3.98 (m, 4H); 3.55-3.65(m, 1H); 3.43-3.50 (m, 3H); 3.30-3.43 (m, 8H); 1.45-1.60 (m, 2H);1.18-1.38 (m, 30H); 0.89 (t, J=7 Hz, 3H). MS (ESI): 718.54 [M−H]—.

Example 37—Hexadecyloxypropyl(S)-9-[3-methoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (32)

Hexadecyloxypropyl(S)-9-[3-methoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (32) wassynthesized (procedure C) from(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine andhexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate. 71% yield. ¹HNMR (CDCl₃/methanol-d₄), δ:7.94 (s, 1H); 7.49-7.55 (m, 2H); 7.24-7.40(m, 3H); 5.55 (s, 2H); 4.30-4.40 (m, 1H); 4.17-4.22 (m, 1H); 3.80-3.92(m, 3H); 3.72-3.92 (m, 1H); 3.55-3.62 (m, 1H); 3.40-3.52 (m, 4H);3.28-3.40 (m, 2H); 3.37 (s, 3H); 1.75-1.85 (m, 2H); 1.44-1.60 (m, 2H);1.16-1.38 (m, 26H); 0.89 (t, J=7 Hz, 3H). MS (ESI): 706.50 [M+H]⁺.

Example 38—Hexadecyloxypropyl(R,S)-9-[3-ethoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (33)

Hexadecyloxypropyl(R,S)-9-[3-ethoxy-2-phosphonomethoxy)propyl]-6-O-benzylguanine (33) wassynthesized (procedure C) from(R,S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-benzylguanine andhexadecyloxypropyl p-toluenesulfonyloxymethylphosphonate. 42% yield). ¹HNMR (CDCl₃/methanol-d₄), δ 7.95 (s, 1H); 7.48-7.52 (m, 2H); 7.30-7.40(m, 3H); 5.56 (s, 2H); 4.34-4.40 (m, 1H); 4.19-4.26 (m, 1H); 3.77-3.93(m, 4H); 3.58-3.66 (m, 1H); 3.47-3.55 (m, 5H); 3.35-3.45 (m, 3H);1.78-1.85 (m, 2H); 1.48-1.55 (m, 2H); 1.17-1.28 (m, 29H); 0.89 (t, J=7Hz, 3H). MS (ESI): 718.46 [M−H]—.

Example 39—General procedure E. Synthesis ofAlkoxyalkyl-9-[(3-alkoxy-2-phosphonomethoxy)propyl]guanine (34-37)

The protected guanine compounds (30-33) (0.71 mmol) were added to 10%trifluoroacetic acid/CH₂Cl₂ and the mixture was stirred at roomtemperature for 2 days. The solvent was removed in vacuo and the residuepurified by flash column chromatography on silica gel. The column waseluted with 20% MeOH/CH₂Cl₂ and the crude products were recrystallizedfrom water to give the alkoxyalkyl9-[(3-alkoxy-2-phosphonomethoxy)propyl]guanine derivatives (34-37).

Example 40—Octadecyloxyethyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]guanine (ODE-(S)-MPMPG) (34)

Octadecyloxyethyl (S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]guanine(ODE-(S)-MPMPG) (34). Deprotection of 30 gave 34 as a white powder. 93%yield. ¹H NMR (CDCl₃/methanol-d₄), 7.82 (s, 1H); 4.24-4.36 (m, 1H);4.10-4.28 (m, 1H); 3.95-4.05 (m, 2H); 3.78-3.90 (m, 2H); 3.62-3.73 (m,1H); 3.52-3.60 (m, 2H); 3.40-3.50 (m, 2H); 3.25-3.40 (m, 3H); 1.45-1.60(m, 2H); 1.18-1.38 (m, 30H); 0.89 (t, J=7 Hz, 3H). MS (ESI): 628.44[M−H]⁻. HRMS (ESI−) calcd. for C₃₀H₅₅N₅O₇P [M−H]⁻ 628.3845. found628.3846 (E=0.2 ppm). HPLC analysis: retention time 21.10, purity 96.2%.

Example 41—Octadecyloxyethyl(R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]guanine (ODE-(R)-MPMPG) (35)

Octadecyloxyethyl (R)-9-[(3-methoxy-2-phosphonomethoxy)propyl]guanine(ODE-(R)-MPMPG) (35). Deprotection of 31 gave 35 as a white powder. 67%yield. ¹H NMR (CDCl₃/methanol-d₄), 8.07 (s, 1H, H-8); 7.51 (s, 2H,—NH₂); 4.34 (dd, 1H, H-1′a, J_(1′a2′)=3.9 Hz, J_(gem)=14.6 Hz); 4.13(dd, 1H, H-1′b, J_(1′b2′)=6.4 Hz, J_(gem)=14.3 Hz); 4.00 (m, 2H,—P—O—CH₂—); 3.87 (dd, 1H, —CH_(a)—P—, J_(P,CHa)=8.7 Hz, J_(gem)=12.9Hz); 3.68 (dd, 1H, —CH_(b)—P—, J_(P,CHb)=9.6 Hz, J_(gem)=12.8 Hz); 3.59(t, 2H, —CH₂—O—CH₂); 3.46 (d+t, 4H, —CH₂—O—CH₂+H-3′); 3.38 (s, 3H,—OCH₃); 1.50-1.62 (m, 2H, —O—CH₂CH₂(CH₂)₁₅—); 1.27 (m, 30H, —(CH₂)₁₅—);0.89 (t, J=7 Hz, 3H, —CH₃). MS (ESI+): 630.29 [M+H]⁺; HRMS (ESI−) calcd.for C₃₀H₅₅N₅O₇P [M−H]⁻ 628.3845. found 628.3843 (E=−0.3 ppm). HPLCanalysis: retention time 22.33 min., purity 92.9%.

Example 42—Hexadecyloxypropyl(S)-9-[3-methoxy-2-phosphonomethoxy)propyl]guanine (HDP-(S)-MPMPG) (36)

Hexadecyloxypropyl (S)-9-[3-methoxy-2-phosphonomethoxy)propyl]guanine(HDP-(S)-MPMPG) (36) Deprotection of 32 gave 36 as a white powder. 93%yield. ¹H NMR (CDCl₃/methanol-d₄), 7.83 (s, 1H); 4.26-4.31 (m, 1H);4.06-4.11 (m, 1H); 3.93-3.98 (m, 2H); 3.81-3.86 (m, 2H); 3.60-3.63 (m,2H); 3.48-3.57 (m, 3H); 3.35-3.44 (m, 2H); 3.37 (s, 3H); 1.84-1.89 (m,2H); 1.52-1.58 (m, 2H); 1.15-1.40 (m, 26H); 0.88 (t, J=7 Hz, 3H). MS(ESI): 616.45 [M+H]⁺, 638.40 [M+Na]⁺. HRMS (ESI−) calcd. for C₂₉H₅₃N₅O₇P[M−H]r 614.3688. found 614.3687 (E=−0.2 ppm). HPLC analysis: retentiontime 20.55 min., purity 93.6%.

Example 43—Hexadecyloxypropyl(R,S)-9-[3-ethoxy-2-phosphonomethoxy)propyl]guanine (HDP-(R,S)-EPMPG)(37)

Hexadecyloxypropyl (R,S)-9-[3-ethoxy-2-phosphonomethoxy)propyl]guanine(HDP-(R,S)-EPMPG) (37). Deprotection of 33 gave 37. 88% yield. ¹H NMR(CDCl₃/methanol-d₄), 7.85 (s, 1H); 4.28-4.33 (m, 1H); 4.11-4.17 (m, 1H);3.92-3.97 (m, 2H); 3.79-3.86 (m, 2H); 3.63-3.92 (m, 1H); 3.47-3.56 (m,5H); 3.34-3.42 (m, 3H); 1.83-1.90 (m, 2H); 1.52-1.57 (m, 2H); 1.22-1.40(m, 26H); 1.20 (t, J=7 Hz, 3H); 0.88 (t, J=7 Hz, 3H). MS (EI): 628.40[M−H]⁻. HRMS (ESI−) calcd. for C₃₀H₅₅N₅O₇P [M−H]r 628.3845. found628.3848 (E=0.5 ppm). HPLC analysis: retention time 20.92 min., purity95.1%.

Example 44—Cytosine Derivative (40)

A scheme useful for synthesis of cytosine containing compounds describedherein is provided in Scheme 4 following, with reagents and conditionsas follows: a) NaH, (S)-methyl glycidyl ether, N,N-DMF, 100° C., 6 h; b)octadecyloxyethyl (ODE) p-toluenesulfonyloxymethylphosphonate; c) 80% aqacetic acid, 60° C., 2 h.

Example45—(S)-1-[(3-methoxy-2-hydroxy)propyl]-N4-monomethoxytritylcytosine (38)

(S)-1-[(3-methoxy-2-hydroxy)propyl]-N⁴-monomethoxytritylcytosine (38)was synthesized from N⁴-monomethoxytritylcytosine⁴ and (S)-methylglycidyl ether (procedure A). 91% yield. ¹H NMR (CDCl₃/methanol-d₄), δ7.45-7.67 (m, 14H); 7.17 (d, J=6 Hz, 1H); 5.82 (d, J=6 Hz, 1H);4.30-4.40 (m, 2H); 4.12 (s, 3H); 3.80-3.92 (m, 1H); 3.65-3.75 (m, 2H);3.65 (s, 3H).

Example 46—Octadecyloxyethyl(S)-1-[(3-methoxy-2-phosphonomethoxy)propyl]-N4-monomethoxytritylcytosine(39)

Octadecyloxyethyl(S)-1-[(3-methoxy-2-phosphonomethoxy)propyl]-N⁴-monomethoxytritylcytosine(39) was synthesized from(S)-9-[(3-methoxy-2-hydroxy)propyl]-N⁴⁻monomethoxytritylcytosine (38)and octadecyloxyethyl p-toluenesulfonyloxymethylphosphonate (procedureC). 45% yield ¹H NMR (CDCl₃/methanol-d₄), δ 7.10-7.40 (m, 14H); 6.85 (d,J=6 Hz, 1H); 5.52 (d, J=6 Hz, 1H); 4.20-4.39 (m, 2H); 3.77-4.02 (m, 4H);3.55-3.65 (m, 1H); 3.43-3.52 (m, 3H); 3.30-3.45 (m, 8H); 1.45-1.65 (m,2H); 1.18-1.40 (m, 30H); 0.89 (t, J=7 Hz, 3H). MS (ESI): 860.55 [M−H]⁻.

Example 47-Octadecyloxyethyl(S)-1-[(3-methoxy-2-phosphonomethoxy)propyl]cytosine, sodium salt (40)(ODE-(S)-MPMPC)

Octadecyloxyethyl (S)-1-[(3-methoxy-2-phosphonomethoxy)propyl]cytosine,sodium salt (40) (ODE-(S)-MPMPC) Octadecyloxyethyl(S)-1-[(3-methoxy-2-phosphonomethoxy)propyl]-N⁴-monomethoxytritylcytosine(39) (0.26 g, 0.60 mmol) was added 15 to 80% aq acetic acid and heatedto 60° C. for 2 hours. After cooling, the solvent was removed in vacuoand the residue purified by flash column chromatography on silica gel.Elution with 20% MeOH/CH₂Cl₂ gave the product (0.1 g, 55%). ¹H NMR(CDCl₃/methanol-d₄) δ 7.80 (d, J=6 Hz, 1H); 6.00 (d, J=6 Hz, 1H);4.04-4.15 (m, 4H); 3.55-3.68 (m, 3H); 3.42-3.53 (m, 2H); 3.35-3.42 (m,4H); 1.50-1.65 (m, 2H); 1.18-1.38 (m, 30H); 0.88 (t, J=7 Hz, 3H). MS(ESI+): 590.33 [M+H]⁺, 612.34 [M+Na]⁺. HRMS (ESI−) calcd. forC₂₉H₅₅N₃O₇P [M−H]⁻ 588.3783. found 588.3784 (E=−0.2 ppm). HPLC analysis:retention time 22.75 min., purity 90.9%.

Example 48-Methoxypurine Derivatives (43-44)

A scheme useful for synthesis of methoxypurine containing compoundsdescribed herein is provided in Scheme 5 following, with reagents andconditions as follows: a) NaH, (S)-methyl glycidyl ether, N,N-DMF, 100°C., 6 h; b) sodium t-butoxide, hexadecyloxypropyl (HDP)p-toluenesulfonyloxymethylphosphonate, N,N-DMF, 80° C.

Example 49—(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-methoxypurine (41)

(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-methoxypurine (41) Reaction of6-methoxypurine (TCI America, Portland, Oreg.) with (S)-methyl glycidylether according to procedure A gave compound 41. 67% yield. ¹H NMR(methanol-d₄) δ 8.51 (s, 1H, H-8), 8.24 (s, 1H, H-2), 4.74 (dd, 1H,J_(1′a2′)=3.8 Hz, J_(gem)=14.2 Hz), 4.28 (dd, 1H, J_(1′b2′)=8 Hz,J_(gem)=14.2 Hz), 4.18 (s, 3H, Ar—OCH₃), 4.14 (m, 1H, H-2′), 3.42 (d,2H, J_(3′2′)=5.2 Hz), 3.37 (s, 3H, —CH₂—OCH₃).

Example 50—(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-methylguanine (42)

(S)-9-[(3-methoxy-2-hydroxy)propyl]-6-O-methylguanine (42) Reaction of6-O-methylguanine (Aldrich Chem.) with (S)-methylglycidyl ether(Procedure A) gave compound 42. 78% yield. ¹H NMR (methanol-d₄) δ 7.81(s, 1H, H-8); 4.35 (dd, 2H, H-1′); 4.15 (m, 1H, H-2′); 4.05 (s, 3H,Ar—OCH₃); 3.39 (d, 2H, H-3′); 3.35 (s, 3H, —OCH₃). MS (ESI): m/z 254.08[M+H]⁺.

Example 51—Hexadecyloxypropyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-methoxypurine(HDP-(S)-MPMPMP) (43)

Hexadecyloxypropyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-methoxypurine(HDP-(S)-MPMPMP) (43) Reaction of compound 41 with hexadecyloxypropylp-toluenesulfonyloxymethylphosphonate according to procedure C affordedcompound 43. 29% yield. ¹H NMR (methanol-d₄) δ 8.51 (s, 1H, H-8); 8.44(s, 1H, H-2); 4.56 (dd, 1H, H-1′_(a), J_(1′a,2′)=3.6 Hz, J_(gem)=14.0Hz); 4.44 (dd, 1H, H-1′_(b), J_(1′b,2′)=6.6 Hz, J_(gem)=14.6 Hz); 4.17(s, 3H, Ar—OCH₃); 3.96 (m, 1H, H-2′); 3.86 (t, 1H, P—O—CH_(a), J=6.4Hz); 3.84 (t, 1H, P—O—CH_(b), J=6.4 Hz); 3.78 (dd, 1H, —CH_(a)—P—,J_(P,CH)=9.2 Hz, J_(gem)=12.8 Hz); 3.60 (dd, 1H, —CH_(b)—P—,J_(P,CH)=9.6 Hz, J_(gem)=12.8 Hz); 3.44 (m, 1H, H-2′); 3.43 (t, 2H,—CH₂—O—CH₂—); 3.36 (t, 2H, —CH₂—O—CH2-); 3.32 (s, 3H, —OCH₃); 1.76(pentet, 2H, —O—CH₂CH₂CH₂—O—); 1.49 (m, 2H, —CH₂—O—CH₂CH₂(CH₂)₁₃—); 1.28(m, 26H, —(CH₂)₁₃—); 0.89 (t, 3H, —CH₃). MS (ESI−) m/z 613.46 [M−H]⁻.HRMS (ESI−) calcd. for C₃₀H₅₄N₄O₇P [M−H]⁻ 613.3736. found 613.3739(E=0.5 ppm).

Example 52—Hexadecyloxypropyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-O-methylguanine(HDP-(S)-MPMPOMG) (44)

Hexadecyloxypropyl(S)-9-[(3-methoxy-2-phosphonomethoxy)propyl]-6-O-methylguanine(HDP-(S)-MPMPOMG) (44). Reaction of compound 42 with hexadecyloxypropylp-toluenesulfonyloxymethylphosphonate according to procedure C affordedcompound 44. 34% yield. ¹H NMR (methanol-d₄) δ 7.95 (s, 1H, H-8), 4.34(dd, 1H, H-1′a, J_(1′a2′)=4 Hz, J_(gem)=14.4 Hz); 4.22 (dd, 1H, H-1′b,J_(1′b2′)=6.4 Hz, J_(gem)=14.4 Hz); 4.04 (s, 3H, Ar—OCH₃); 3.91 (m, 1H,H-2′); 3.87 (t, 1H, P—O—CH_(a)—, J=6.4 Hz); 3.86 (t, 1H, P—O—CH_(b)—,J=6.4 Hz); 3.75 (dd, 1H, —CH_(a)—P—, J_(CH,P)=9.4 Hz, J_(gem)=13 Hz);3.64 (dd, 1H, —CH_(b)—P—, J_(CH,P)=9.2 Hz, J_(gem)=12.8 Hz); 3.44 (t,2H, —CH₂—O—); 3.43 (d, 2H, H-3′); 3.35 (t, 2H, —O—CH₂); 3.34 (s, 3H,—OCH₃); 1.78 (pentet, 2H, —O—CH₂CH₂CH₂—O—); 1.50 (m, 2H,—OCH₂CH₂(CH₂)₁₃—); 1.27 (m, 26H, (CH₂)₁₃); 0.89 (t, 3H, —CH₃). MS (ESI):m/z 630.35 [M+H]⁺; 628.37 [M−H]⁻. HRMS (ESI−) calcd. for C₃₀H₅₅N₅O₇P[M−H]⁻ 628.3845. found 628.3847 (E=0.3 ppm). HPLC analysis: retentiontime 21.60 min., purity 97.0%.

Example 53—Hexadecyloxypropyl(R,S)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine (HDP-(R,S)-FPMPA)

Sodium hydride (0.10 g, 4.37 mmol) was added to a solution of adenine(1.78 g, 13.1 mmol) in anhydrous N,N-DMF (60 mL), then(R,S)-epifluorohydrin (1.0 g, 13.1 mmol) was added to the mixture thatwas stirred and heated to 100° C. for 6 hours. After cooling, thesolvent was removed in vacuo and the residue was purified by flashcolumn chromatography on silica gel. Elution of the column with 10%MeOH/CH₂Cl₂ gave (R,S)-9-[(3-fluoro-2-hydroxy)propyl]adenine in 56%yield (1.58 g). ¹H NMR (CDCl₃/methanol-d₄), δ: 8.25 (s, 1H); 8.06 (s,1H); 4.35-4.55 (m, 3H); 4.15-4-30 (m, 2H).

Bromotrimethylsilane (2.10 mL, 16.60 mmol) was added dropwise to asuspension of (R,S)-9-[(3-fluoro-2-hydroxy)propyl]adenine (1.56 g, 7.38mmol) in dry pyridine (30 mL). The mixture was stirred 15 min until itbecame clear, then monomethoxytrityl chloride (2.60 g, 8.4 mmol) and4-(dimethylamino)-pyridine (0.06 g, 0.50 mmol) were added and stirringwas continued overnight. The mixture was cooled with an ice bath and H₂O(1 mL) was added. Stirring was continued 10 min., then con. NH₄OH (1 mL)was added and the reaction was stirred 30 additional min. The mixturewas allowed to warm up to room temperature and filtered through a pad ofCelite®. The filtrate was evaporated in vacuo and the residue waspurified by flash column chromatography on silica gel. Gradient elution100% hexanes to 100% ethyl acetate afforded N⁶-monomethoxytrityl(R,S)-9-[(3-fluoro-2-hydroxy)propyl]adenine (2.15 g, 60% yield) ¹H NMR(CDCl₃/methanol-d₄), δ: 7.99 (s, 1H); 7.98 (s, 1H); 7.15-7.37 (m, 12H);6.75-6.83 (m, 2H); 4.40-4.54 (m, 2H); 4.19-4.25 (m, 3H); 3.79 (s, 3H).

Sodium t-butoxide (0.20 g, 2.0 mmol) was added to a solution ofN⁶-monomethoxytrityl (R,S)-9-[(3-fluoro-2-hydroxy)propyl]adenine (0.48g, 1.0 mmol) and hexadecyloxypropylp-toluenesulfonyloxymethylphosphonate (0.82 g, 1.5 mmol, prepared asdescribed by Beadle, et al., 2006, Id.) in N,N-DMF (20 mL). in N,N-DMF(100 mL). The mixture was heated to 80° C. and kept overnight. Aftercooling, the solvents were evaporated in vacuo and the residue waspurified by flash column chromatography on silica gel. The column waseluted with gradient chloroform 100%-chloroform-methanol (20%) to givehexadecyloxypropyl (R,S)-9-[(3-fluoro-2-phosphonomethoxy)propyl]N⁶-monomethoxytrityl adenine (0.26 g, 30% yield). ¹H NMR(CDCl₃/methanol-d₄), δ: 8.18 (s, 1H); 7.98 (s, 1H); 7.18-7.38 (m, 12H);6.79-6.81 (m, 2H); 4.40-4.68 (m, 3H); 4.22-4.40 (m, 2H); 3.85-4.05 (m,2H); 3.79 (s, 3H); 3.58-3.65 (m, 2H); 3.21-3.25 (m, 2H); 3.15-3.19 (m,2H); 1.79-1.87 (m, 2H); 1.43-1.59 (m, 2H); 1.20-1.38 (m, 26H); 0.88 (t,J=7 Hz, 3H). MS (EI): 858.59 (M−H)⁻.

The product (0.26 g, 0.30 mmol) was added to 80% acetic acid and heatedto 60° C. overnight. After cooling, the solvent was removed in vacuo andthe residue purified by flash column chromatography on silica gel.Elution with 20% MeOH/CH₂Cl₂ gave hexadecyloxypropyl(R,S)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine (0.15 g, 88%yield). ¹H NMR (CDCl₃/methanol-d₄), δ: 8.30 (s, 1H); 8.25 (s, 1H);4.45-4.68 (m, 3H); 4.35-4.42 (m, 2H); 3.78-4.08 (m, 4H); 3.43-3.55 (m,2H); 3.17-3.23 (m, 2H); 1.81-1.87 (m, 2H); 1.43-1.62 (m, 2H); 1.18-1.40(m, 26H); 0.89 (t, J=7 Hz, 3H). MS (EI): 586.35 (M−H)⁻.

Example 54—Octadecyloxyethyl(S)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine (ODE-(S)-FPMPA)

Sodium hydride (0.08 g, 2.0 mmol) was added to a solution of adenine(1.35 g, 10 mmol) in anhydrous N,N-DMF (60 mL), then (S)-trityl glycidylether (3.16 g, 10 mmol) was added to the mixture that was stirred andheated to 100° C. for 6 hours. After cooling, the solvent was removed invacuo and the residue was purified by flash column chromatography onsilica gel. Elution of the column with 10% MeOH/CH₂Cl₂ gave9-[(3-trityloxy-2-hydroxy)propyl]adenine in 75% yield (3.4 g). ¹H NMR(CDCl₃/methanol-d₄), δ: 8.20 (s, 1H); 7.90 (s, 1H); 7.42-7.54 (m, 6H);7.24-7.32 (m, 9H); 4.43-4.64 (m, 1H); 4.29-4-33 (m, 1H); 4.15-4.18 (m,1H); 3.19-3.35 (m, 1H); 3.09-3.13 (m, 1H).

Bromotrimethylsilane (1.90 mL, 14.65 mmol) was added dropwise to asuspension of (S)-9-[(3-trityloxy-2-hydroxy)propyl]adenine (2.94 g, 6.5mmol) in dry pyridine (30 mL). The mixture was stirred 15 min. until itbecame clear, then monomethoxytrityl chloride (2.30 g, 7.4 mmol) and4-(dimethylamino)-pyridine (0.05 g, 0.46 mmol) were added and stirringwas continued overnight. The mixture was cooled with an ice bath and H₂O(1 mL) was added. Stirring was continued 10 min., then con. NH₄OH (1 mL)was added and the reaction was stirred 30 additional min. The mixturewas allowed to warm up to room temperature and filtered through a pad ofCelite®. The filtrate was evaporated in vacuo and the residue waspurified by flash column chromatography on silica gel. Gradient elution100% hexanes to 100% ethyl acetate afforded(S)-9-[(3-trityloxy-2-hydroxy)propyl] N⁶-monomethoxytrityl-adenine (4.37g, 93% yield) ¹H NMR (CDCl₃/methanol-d₄), δ: 8.14 (s, 1H); 7.99 (s, 1H);7.44-7.61 (m, 27H); 6.99-7.03 (m, 2H); 4.52-4.69 (m, 1H); 4.40-4.52 (m,1H); 4.25-4.40 (m, 1H); 3.99 (s, 3H); 3.35-3.45 (m, 1H); 3.25-3.35 (m,1H).

Sodium t-butoxide (0.96 g, 10.0 mmol) was added to a solutionof(S)-9-[(3-trityloxy-2-hydroxy)propyl] N⁶-monomethoxytrityl-adenine(3.6 g, 5.0 mmol) and diethyl p-toluenesulfonyloxymethylphosphonate (3.2g, 10.0 mmol,) in N,N-DMF (100 mL). The mixture was heated to 80° C. andkept overnight. After cooling, the solvents were evaporated in vacuo andthe residue was purified by flash column chromatography on silica gel.The column was eluted with gradient chloroform 100%-chloroform-methanol(20%) to give diethyl (S)-9-[3-trityloxy-2-phosphonomethoxy)propyl]N⁶-monomethoxytrityl-adenine (2.53 g, 57% yield). ¹H NMR(CDCl₃/methanol-d₄), δ: 7.94 (s, 1H); 7.92 (s, 1H); 7.41-7.50 (m, 7H);7.21-7.35 (m, 20H); 6.79-6.81 (m, 2H); 4.37-4.51 (m, 2H); 3.89-4.12 (m,6H); 3.79 (s, 3H); 3.34-3.38 (m, 2H); 3.15-3.19 (m, 1H); 1.29 (t, J=7Hz, 3H); 1.23 (t, J=7 Hz, 3H).

The product (2.52 g, 2.88 mmol) was added to 80% acetic acid and heatedto 60° C. overnight. After cooling, the solvent was removed in vacuo andthe residue purified by flash column chromatography on silica gel.Elution with 20% MeOH/CH₂Cl₂ gave diethyl(S)-9-[3-hydroxy-2-phosphonomethoxy)propyl]adenine (0.84 mg, 82% yield).¹H NMR (CDCl₃/methanol-d₄), δ: 8.26 (s, 1H); 8.04 (s, 1H); 4.37-4.50 (m,2H); 4.05-4.11 (m, 4H); 3.88-4.00 (m, 1H); 3.75-3.84 (m, 2H); 3.59-3.70(m, 2H); 1.33 (t, J=7 Hz, 3H); 1.29 (t, J=7 Hz, 3H). MS (EI): 360.35(M+H)⁺, 382.32 (M+Na)⁺.

Diethyl (S)-9-[3-hydroxy-2-phosphonomethoxy)propyl]adenine (0.45 g, 1.25mmol) was dissolved in dry pyridine (10 mL) and treated withmethanesulfonyl chloride (0.12 mL, 1.50 mmol). After 1 hour. Anadditional equivalent of methanesulfonyl chloride was added, followed anhour later by a third equivalent. The pyridine was evaporated. Theresidue was purified by column chromatography on silica gel. Eluent:ethyl acetate 100%, ethyl acetate (80%)-10% ammonium hydroxide inethanol −20%. The yield was 0.40 g (89%). ¹H NMR (CDCl₃/methanol-d₄), δ:8.26 (s, 1H); 8.08 (s, 1H); 4.48-4.56 (m, 2H); 4.37-4.44 (m, 1H);4.25-4.30 (m, 1H); 3.99-4.18 (m, 6H); 3.76-3.83 (m, 1H); 3.16 (s, 3H);1.33 (t, J=7 Hz, 3H); 1.28 (t, J=7 Hz, 3H). MS (EI): 438.26 (M+H)⁺,460.03 (M+Na)⁺.

Obtained methansulfonate (0.40 g, 0.91 mmol) was suspended in themixture acetonitrile-toluene 1:1 (30 mL) and treated withtetramethylammonium bifluoride (0.26 g, 2.73 mmol) and heated at about100° C. for 1 hour. The solvent were evaporated. The residue waspurified by column chromatography on silica gel. Eluent: ethyl acetate100%, ethyl acetate (80%)-10% ammonium hydroxide in ethanol −20%. Theyield was 0.33 g (100%). ¹H NMR (CDCl₃/methanol-d₄), δ: 8.26 (s, 1H);8.06 (s, 1H); 4.37-4.77 (m, 4H); 3.99-4.17 (m, 6H); 3.76-3.83 (m, 1H);1.32 (t, J=7 Hz, 3H); 1.28 (t, J=7 Hz, 3H). MS (EI): 362.06 (M+H)⁺.

Diethyl (S)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine (0.33 g, 0.91mmol) was dissolved in dry N,N-DMF (5 ml), and bromotrimethylsilane(0.26 mL, 1.90 mmol) was added to the solution. The mixture was stirredat room temperature overnight. The solvents were evaporated andcoevaporated with toluene (20 mL). Methanol-water 1:1 (20 mL) were addedto the residue. The mixture was stirred at room temperature for 30 min,the solvents were evaporated; the residue was purified by ion-exchangechromatography on DEAE Sephadex A-25 (HCOO⁻ form). Eluent: gradientwater −1M formic acid. The yield was 0.18 g (65%). ¹H NMR(D₂O/methanol-d₄), δ: 8.45 (s, 1H); 8.38 (s, 1H); 4.40-4.74 (m, 4H);4.04-4.19 (m, 1H); 3.78-3.83 (m, 1H); 3.62-3.72 (m, 1H). MS (EI): 304.00(M+H)⁺.

To the solution of (S)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine(0.09 g, 0.29 mmol) and octadecyloxyethanol (0.11 g, 0.35 mmol) in drypyridine (20 mL) N,N-dicyclohexylcarbodiimide (0.14 g, 0.70 mmol) wasadded. The mixture was stirred at 80° C. for 5 hours. The solvents wereevaporated and then the residue was purified by column chromatography onsilica gel. Elution with 20% MeOH/CH₂Cl₂ gave octadecyloxyethyl(S)-9-[3-fluoro-2-phosphonomethoxy)propyl]adenine (0.04 g, 23% yield).¹H NMR (CDCl₃/methanol-d₄), δ: 8.31 (s, 1H); 8.18 (s, 1H); 4.50-4.75 (m,2H); 4.43-4.49 (m, 1H); 4.07-4.16 (m, 1H); 3.98-4.17 (m, 2H); 3.84-3.72(m, 1H); 3.56-3.60 (m, 2H); 3.42-3.48 (m, 2H); 3.35-3.37 (m, 1H);1.52-1.60 (m, 2H); 1.20-1.34 (m, 30H); 0.88 (t, J=7 Hz, 3H). MS (EI):600.30 (M−H)⁻.

Example 55—Octadecyloxyethyl(R)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine (ODE-(R)-FPMPA)

Sodium hydride (0.16 g, 4.0 mmol) was added to a solution of adenine(2.70 g, 20 mmol) in anhydrous N,N-DMF (60 mL), then (R)-trityl glycidylether (6.18 g, 19.5 mmol) was added to the mixture that was stirred andheated to 100° C. for 6 hours. After cooling, the solvent was removed invacuo and the residue was purified by flash column chromatography onsilica gel. Elution of the column with 10% MeOH/CH₂Cl₂ gave (R)9-[(3-trityloxy-2-hydroxy)propyl]adenine in 82% yield (7.2 g). ¹H NMR(CDCl₃/methanol-d₄), δ: 8.20 (s, 1H); 7.91 (s, 1H); 7.42-7.56 (m, 6H);7.22-7.32 (m, 9H); 4.48-4.50 (m, 1H); 4.50-4.63 (m, 1H); 4.15-4.18 (m,1H); 3.20-3.25 (m, 1H); 3.09-3.13 (m, 1H).

Bromotrimethylsilane (4.50 mL, 35.0 mmol) was added dropwise to asuspension of (R) 9-[(3-trityloxy-2-hydroxy)propyl]adenine (7.20 g,15.95 mmol) in dry pyridine (60 mL). The mixture was stirred 15 min.until it became clear, then monomethoxytrityl chloride (5.60 g, 18.0mmol) and 4-(dimethylamino)-pyridine (0.13 g, 1.1 mmol) were added andstirring was continued overnight. The mixture was cooled with an icebath and H₂O (1 mL) was added. Stirring was continued 10 min., then con.NH₄OH (1 mL) was added and the reaction was stirred 30 additional min.The mixture was allowed to warm up to room temperature and filteredthrough a pad of Celite®. The filtrate was evaporated in vacuo and theresidue was purified by flash column chromatography on silica gel.Gradient elution 100% hexanes to 100% ethyl acetate afforded (R)9-[(3-trityloxy-2-hydroxy)propyl] N⁶-monomethoxytrityl adenine (5.97 g,52% yield) ¹H NMR (CDCl₃/methanol-d₄), δ: 7.93 (s, 1H); 7.83 (s, 1H);7.41-7.47 (m, 5H); 7.20-7.03 (m, 20H); 6.79-6.82 (m, 2H); 4.37-4.41 (m,1H); 4.23-4.29 (m, 1H); 4.10-4.17 (m, 1H); 3.79 (s, 3H); 3.18-3.21 (m,1H); 3.10-3.13 (m, 1H).

Sodium t-butoxide (1.05 g, 11.0 mmol) was added to a solution of(R)-9-[(3-trityloxy-2-hydroxy)propyl] N⁶-monomethoxytrityl-adenine (5.45g, 7.23 mmol) and diethyl p-toluenesulfonyloxymethylphosphonate (4.80 g,15.0 mmol,) in N,N-DMF (100 mL). The mixture was heated to 80° C. andkept overnight. After cooling, the solvents were evaporated in vacuo andthe residue was purified by flash column chromatography on silica gel.The column was eluted with gradient chloroform 100%-chloroform-methanol(20%) to give diethyl(R)—N⁶-monomethoxytrityl-9-[3-tityloxy-2-phosphonomethoxy)propyl]adenine (6.28 g, 99% yield). ¹H NMR (CDCl₃/methanol-d₄), δ: 7.95 (s,1H); 7.92 (s, 1H); 7.41-7.48 (m, 7H); 7.21-7.35 (m, 20H); 6.79-6.81 (m,2H); 4.37-4.49 (m, 2H); 3.83-4.25 (m, 6H); 3.78 (s, 3H); 3.36-3.40 (m,2H); 3.15-3.20 (m, 1H); 1.28 (t, J=7 Hz, 3H); 1.23 (t, J=7 Hz, 3H).

The product (6.30 g, 7.23 mmol) was added to 80% acetic acid and heatedto 60° C. overnight. After cooling, the solvent was removed in vacuo andthe residue purified by flash column chromatography on silica gel.Elution with 20% MeOH/CH₂Cl₂ gave diethyl(R)-9-[3-hydroxy-2-phosphonomethoxy)propyl]adenine (1.85 g, 71% yield).¹H NMR (CDCl₃/methanol-d₄), δ: 8.25 (s, 1H); 8.08 (s, 1H); 4.42-4.50 (m,1H); 4.36-4.40 (m, 1H); 3.95-4.15 (m, 5H); 3.78-3.90 (m, 2H); 3.60-3.77(m, 2H); 1.31 (t, J=7 Hz, 3H); 1.27 (t, J=7 Hz, 3H).

Diethyl (R)-9-[3-hydroxy-2-phosphonomethoxy)propyl]adenine (1.83 g, 5.10mmol) was dissolved in dry pyridine (50 mL) and treated withmethanesulfonyl chloride (0.47 mL, 6.10 mmol). After 1 hour. Anadditional equivalent of methanesulfonyl chloride was added, followed anhour later by a third equivalent. The pyridine was evaporated. Theresidue was purified by column chromatography on silica gel. Eluent:ethyl acetate 100%, ethyl acetate (80%)-10% ammonium hydroxide inethanol −20%. The yield was 1.94 g (88%). ¹H NMR (CDCl₃/methanol-d₄), δ:8.26 (s, 1H); 8.08 (s, 1H); 4.48-4.56 (m, 2H); 4.37-4.44 (m, 1H);4.25-4.32 (m, 1H); 4.00-4.18 (m, 6H); 3.78-3.82 (m, 1H); 3.16 (s, 3H);1.32 (t, J=7 Hz, 3H); 1.28 (t, J=7 Hz, 3H).

Obtained methansulfonate (0.44 g, 1.00 mmol) was suspended in themixture acetonitrile-toluene 1:1 (30 mL) and treated withtetramethylammonium bifluoride (0.28 g, 2.80 mmol) and heated at about100° C. for 1 hour. The solvents were evaporated. The residue waspurified by column chromatography on silica gel. Eluent: ethyl acetate100%, ethyl acetate (80%)-10% ammonium hydroxide in ethanol −20%. Theyield was 0.36 g (100%). ¹H NMR (CDCl₃/methanol-d₄), δ: 8.26 (s, 1H);8.07 (s, 1H); 4.37-4.80 (m, 4H); 4.00-4.17 (m, 6H); 3.76-3.83 (m, 1H);1.32 (t, J=7 Hz, 3H); 1.28 (t, J=7 Hz, 3H). MS (EI): 362.05 (M+H)⁺;383.96 (M+Na)⁺.

Diethyl (R)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine (0.36 g, 1.00mmol) was dissolved in dry N,N-DMF (5 ml), and bromotrimethylsilane(0.40 mL, 3.00 mmol) was added to the solution. The mixture was stirredat room temperature overnight. The solvents were evaporated andcoevaporated with toluene (20 mL). Methanol-water 1:1 (20 mL) were addedto the residue. The mixture was stirred at room temperature for 30 min,the solvents were evaporated; the residue was purified by ion-exchangechromatography on DEAE Sephadex A-25 (HCOO⁻ form). Eluent: gradientwater −1M formic acid. The yield was 0.18 mg (60%). ¹H NMR (D₂O), δ:8.33 (s, 1H); 8.23 (s, 1H); 4.65-4.74 (m, 1H); 4.38-4.60 (m, 3H);4.05-4.15 (m, 1H); 3.50-3.65 (m, 2H). MS (EI): 303.99 (M+H)⁺.

To the solution of (R)-9-[(3-fluoro-2-phosphonomethoxy)propyl]adenine(0.09 g, 0.29 mmol) and octadecyloxyethanol (0.11 g, 0.35 mmol) in drypyridine (20 mL) N,N-dicylcohexylcarbodiimide (0.14 g, 0.70 mmol) wasadded. The mixture was stirred at 50° C. for 2 hours. The solvents wereevaporated and the residue was purified by column chromatography onsilica gel. Elution with 20% MeOH/CH₂Cl₂ gave octadecyloxyethyl(R)-9-[3-hydroxy-2-phosphonomethoxy)propyl]adenine (0.11 g, 65% yield).¹H NMR (CDCl₃/methanol-d4), δ: 8.31 (s, 1H); 8.22 (s, 1H); 4.44-4.77 (m,2H); 4.34-4.42 (m, 1H); 3.97-4.16 (m, 1H); 3.98-4.17 (m, 2H); 3.84-3.72(m, 1H); 3.56-3.60 (m, 2H); 3.42-3.48 (m, 2H); 3.35-3.37 (m, 1H);1.50-1.60 (m, 2H); 1.20-1.38 (m, 30H); 0.88 (t, J=7 Hz, 3H). MS (EI):600.29 (M−H)⁻.

Example 56. Synthesis of (S)-MPMPA diphosphate

To a stirred suspension of9-(S)-[3-methoxy-2-(phosphonomethoxy)propyl]adenine ((S)-MPMPA, 770 mg,2.4 mmol) in pyridine-H₂O (10;1, 10 mL) was added tri-n-butylamine (926mg, 5 mmol). The solution was stirred at room temp 10 min until a clearsolution was obtained, then the solvents were evaporated under vacuum.The residue was dissolved in hexamethylphosphoramide (HMPA, 10 mL) andto this was added 1, 1′-carbonyldiimidazole (810 mg, 5 mmol) and thesolution was stirred for 1 h at 22° C. Methanol was added (270 μL) andafter stirring additional 0.5 h a solution of bis(tri-n-butylammonium)pyrophosphate (1.1 g, 3 mmol) in HMPA (6 mL) was added and the mixturestirred for 18 h. The precipitated inorganic pyrophosphate was removedby filtration and washed with a small volume of HMPA. The HMPA solutionswere combined, diluted with cold water (25 mL) and chromatographed on acolumn of DEAE cellulose (HCO₃— form) using a linear gradient oftriethylammonium hydrogen carbonate (0-0.4 M). UV active fractionscontaining MPMPA diphosphate were combined and lyophilized to give(S)-MPMPA diphosphate triethylammonium salt as a white powder (1.2 g,72% yield).

Example 57—Antiviral Activity Determination of the 50% EffectiveConcentration (EC₅₀) in HCV genotype 1b and 2a replicons

Compounds of the invention were tested for anti-HCV activity aspreviously described using 10,000 replicon cells per well on 96-wellplates. See Wyles, D. L. et al., 2009, Antimicrob. Agents Chemother.53:2660-2662. Values for 50% effective concentration (EC₅₀) and for theminimal concentration required to induce 50% cleavage (CC₅₀) werecalculated for each test compound by linear regression analysis, usingdata combined for all treated cultures. Antiviral and toxicity assaysutilized triplicate cultures for each drug concentration; 12 untreatedcultures were included in each assay.

Example 58—Anti-HCV Activity

Compounds were tested for anti-HCV activity in genotype 1b and 2areplicons as previously described, and their activity was compared withthat of ODE-(S)-HPMPA and HDP-(S)-HPMPA (Table 5 following). See Wyles,D. L., et al., 2007, J Virol, 81:3005-3008. ODE-(S)-MPMPA (15) retainedfull activity against genotype 1b and 2a replicons with EC₅₀ values of1.43±0.38 and 2.38±1.09 μM while the (R) isomer (16) was slightly lessactive with EC₅₀s of 4.65 and 5.33 M. HDP-(S)-MPMPA (17) was slightlyless active than the corresponding ODE ester with EC₅₀s of 2.36 (1b) and4.64 μM (2a). When ethyl or isopropyl substitutions were made at the3′-hydroxyl instead of methyl, the anti-HCV activity dropped slightlywith HDP-(R,S)-EPMPA (18) to EC₅₀s of 7.59 (1b) and 8.87 μM (2a).Without wishing to be bound by any theory, these data suggest thatlarger substitutions are not favored. Cytotoxicity of ODE-(S)-MPMPA wassubstantially lower than that observed with ODE-(S)-HPMPA, CC₅₀>150versus 35.6 μM. Of the various adenine analogs, ODE-(S)-MPMPA had thegreatest selectivity index, >105 with genotype 1b and >63 with genotype2a replicons. The BM4-5 and JFH-1 replicons have been described. Seee.g., Wyles, D. L., et al., 2007, Id.; Date, T., et al., 2004, 1 Biol.Chem., 279:22371-22376.

TABLE 5 Selec- tivity Index Selectivity EC₅₀ (μM) BM4-5 Index CmpdBM4-5(1b) JFH-1 (2a) CC₅₀ (μM) (1b) JFH-1 (2a) 1 1.55 ± 0.50 1.65 ± 0.3335.6 ± 6.8  22.9 21.6 15 1.43 ± 0.38 2.38 ± 1.09 >150 >105 >63 16 4.65 ±0.88 5.33 ± 0.92 >150 >32.3 >28.1 17 2.36 ± 0.37 4.64 ±1.26 >150 >63.6 >32.3 18 7.59 ± 1.31 8.87 ± 2.05  99 ± 0.5 13.0 11.1 1951.2 ± 38.2 98.8 ± 20.8  100 ± 20.8 3.14 NM 23 20.1 ± 1.98 21.4 ± 1.3099.0 ± 13.4 4.94 4.62 24 25.6 ± 4.23 25.8 ± 6.10 >150 >5.86 >5.81 2521.3 ± 3.10 23.6 ± 2.70 91.5 ± 17.8 4.30 3.87 26 18.2 ± 7.09 19.5 ±1.48 >150 >8.2 >7.69 34 8.26 ± 1.30 10.7 ± 1.33 >150 >18.2 >14.0 35 12.6± 1.67 12.4 ± 3.45 >150 >11.9 >12.1 36 22.0 ± 4.97 24.8 ±7.00 >150 >6.82 >6.04 37 25.5 ± 10.4 13.2 ± 3.45 >150 >5.88 >11.440 >150 >150 >150 NM NM 43 8.90 ± 1.22 12.5 ± 3.36 >150 8.04 5.72 4418.1 ± 0.27 17.4 ± 0.30 >150 4.98 5.18

Example 58—Alkoxyalkyl MPMP Esters of Cytosine, Guanine, 2,6-Diaminopurine, 6-Methoxypurine and 6-O-Methylguanine

Also prepared were alkoxyalkyl MPMP esters of cytosine, guanine,2,6-diaminopurine, 6-methoxypurine and 6-O-methylguanine. The mostactive anti-HCV compound was ODE-(S)-MPMPG (34) with EC₅₀ values of 8.26and 10.7 μM against genotype 1b and 2a, respectively; the (R) isomer(35) was slightly less active with EC₅₀s of 12.6 and 12.4 μM. Thesecompounds also had low cytotoxicity with CC₅₀ values >150 μM.HDP-(S)-MPMPMP (43) also exhibited significant activity in the 8.9 to12.5 μM range. HDP-(S)-MPMPOMG (44) and the ODE and HDP esters of both(R) and (S)-MPMPDAP (23-25) were less active with EC₅₀ values rangingfrom 18 to 26 μM while ODE-(S)-MPMPC (40) was inactive.

Example 59—Evaluation in MT-2 Cells

We also evaluated compounds described herein in MT-2 cells infected withHIV-1. See Table 6 following. ODE-(S)-HPMPA (1) was highly active withan EC₅₀ of 0.0001 μM. However, the CC₅₀ was 0.033 μM making it the mostcytotoxic compound in the series. ODE-(S)-MPMPA (15) retainedsubstantial antiviral activity with an EC₅₀ of 0.03 μM and a CC₅₀ of 22μM (selectivity index 733) while HDP-(S)-MPMPA (17) was less active andODE-(R)-MPMPA (16) was considerably less active and selective.Introduction of an ethoxy or isopropoxy at the 3′-hydroxyl position ofthe acyclic moiety (compounds 18, 19) resulted in a loss of antiviralactivity (Table 6).

TABLE 6 Compound EC₅₀ (μM) CC₅₀ (μM) Selectivity Index 1 ODE-(S)-HPMPA0.0001 ± 0.000 (6)  0.033 ± 0.02 (3)  330 15 ODE-(S)-MPMPA  0.03 ± 0.015(3) 22 ± 5 (3)  733 16 ODE-(R)-MPMPA 4.8 ± 3.0 (3) 26.7 ± 11.2 (3) 5.617 HDP-(S)-MPMPA 0.20 ± 0.26 (4) 32 ± 11 (3) 160 18 HDP-(R,S)-EPMPA >1023.6 ± 7.1 (3)  NM 19 HDP-(R,S)-IPPMPA >10 30.3 ± 12.5 (3) NM 23ODE-(S)-MPMPDAP 0.23 ± 0.15     18.0 ± 5.3 (3)  78 24 ODE-(R)-MPMPDAP0.04 ± 0.06 (4) 19.7 ± 9.5 (3)  493 25 HDP-(S)-MPMPDAP 4.6 ± 1.8 (3)22.7 ± 6.8 (3)  4.9 26 HDP-(R,S)-EPMPDAP >10 30.7 ± 11.7 (3) NM 34ODE-(S)-MPMPG 0.20 ± 0.22 (4) 25 ± 13 (3) 125 35 ODE-(R)-MPMPG <1 × 10⁻⁵(3)  44 ± 5.6 (3) >4.4 × 10⁶ 36 HDP-(S)-MPMPG 2.03 ± 0.95 (4) 29.3 ± 3.1(3)  14.4 37 HDP-(R,S)-EPMPG >10 14.9 ± 6.7 (3)  NM 40 ODE-(S)-MPMPC12.7 ± 4.0 (3)  60.7 ± 16 (3)   4.8 43 HDP-(S)-MPMPMP >10 22.0 ± 3.5(3)  NM 44 HDP-(S)-MPMPOMG >10 34.3 ± 7.6 (3)  NM

Example 60—ODE-(R)-MPMPG

Surprisingly, the most active compound was ODE-(R)-MPMPG (35),EC₅₀<1×10⁻⁵ μM and a selectivity index of >4.4 million. See Table 6.Interestingly, the (S) isomer (34) was substantially less active with anEC₅₀ of 0.2 μM. The same pattern was observed with ODE-(R)-MPMPDAP (24)which was more active (EC₅₀=0.4 μM) than the (S) isomer (23). As notedbefore with the adenine analogs, the HDP esters (25, 36) were lessactive. Again, introduction of larger ethyl groups at the 3′-hydroxyl ofthe acyclic chain of these compounds (26, 37) caused a large loss ofanti-HIV activity. ODE-(S)-MPMPC (40) was not highly active (EC₅₀=12.7μM) and HDP-(S)-MPMPMP (43) and HDP-(S)-MPMPOMG (44) were not highlyactive against HIV (EC₅₀>10 μM).

Example 61—ODE-(S)-MPMPA against HCMV and HSV-1

ODE-(S)-MPMPA was also tested against HCMV and HSV-1 using our previousmethods. See Prichard, M. N., et al., 2008, Antimicrob. AgentsChemother., 52:4326-4330. We reported previously that ODE-(S)-HPMPA is apowerful inhibitor of the replication of orthopoxviruses, includingvariola, vaccinia and cowpox, and ectromelia, as well as other dsDNAviruses including human cytomegalovirus (HCMV) and herpes simplex virus,type 1 (HSV-1). See e.g., Beadle, et al., 2006, Id.; Huggins, J. W.,2002, Antiviral Res., 53:A66 (abstract 104); Kern, E. R., et al., 2002,Antimicrob. Agents Chemother. 46:991-995; Buller, R. M., et al., 2004,Virology, 318:474-481; Magee, W. C. et al., 2008, Antimicrob. AgentsChemother. 52:586-597. We examined the effect of blocking the3′-hydroxyl of HPMPA with 3′-methoxy on the compound's antiviralactivity against dsDNA viruses including vaccinia, cowpox, HCMV andHSV-1. See Table 7 following.

TABLE 7 Comparative Antiviral Activity of ODE-(S)-HPMPA versusODE-(S)-MPMPA Against dsDNA Viruses in vitro EC₅₀ (μM) Compound VacciniaCowpox HCMV HSV-1 1 ODE-(S)-HPMPA 0.02 ± 0.01^(a) 0.05 ± 0.04^(a) 0.003± 0.001^(a) <0.0001 15 ODE-(S)-MPMPA 18.3 ± 2.4 >200 1.55 ± 0.4^(b) 45.7 ± 10.1^(b) Fold change 915 >400 516 >45 million ^(a)Data andmethods from Beadle et al.(Id.) ^(b)Data for ODE-(S)-MPMPA vs. HCMV andHSV-1 were obtained by plaque reduction assay in HFF cells as previouslydescribed by Prichard et al. (Id.)

As we reported previously, ODE-(S)-HPMPA had potent antiviral activityagainst these viruses with EC₅₀ values ranging from <0.1 to 20nanomolar. However, ODE-(S)-MPMPA (15) exhibited a dramatic loss ofantiviral activity with EC₅₀ values >400 to >45 million times higherthan those of ODE-(S)-HPMPA (Table 7). We reported previously thatinhibition of vaccinia virus replication occurs by a unique mechanism inwhich (S)-HPMPA diphosphate is incorporated into DNA by the viral E9Lpolymerase. However, the vaccinia polymerase cannot copy across the druglesion in HPMPA containing templates. See Magee, et al., 2008, Id. TheEC₅₀ for vaccinia inhibition by ODE-(S)-HPMPA is 20 nanomolar versus18,300 nanomolar for ODE-(S)-MPMPA, a reduction of 915-fold. See Table7. These findings generally support the principal mechanism which wedescribed previously because incorporation of HPMPA into viral DNA,blocking further copying of the drug-containing chain is not possiblewith ODE-(S)-MPMPA, and any residual antiviral activity with the lattercompound is due to obligatory chain termination. Without wishing to bebound by any theory, it is believed that this is presumably also themechanism of action in cowpox which has a closely related DNApolymerase.

Example 62—Activity in Human Peripheral Blood Mononuclear Cells

Compound ODE-(S)-MPMPA was tested in Human Peripheral Blood MononuclearCells (PBMCs) infected with HIV-1_(NL43). The resulting EC₅₀ was about 5nM, and the CC50 was >10 uM, giving a selectivity of >2000. HDP-estersof MPMPA and MPMPG were also active against HIV-1 with EC₅₀ values of0.2 and 2.0 μM. Thus, ODE-(S)-HPMPA was highly active and selective inHIV-1 infected human PBMCs; HDP-(S)-MPMPA and HDP-(S)-MPMPG were alsoactive and selective. See Table 8 following.

TABLE 8 Effect of ODE-(S)-MPMPA and Related Compounds on HIV-1Replication in Human Peripheral Blood Mononuclear Cells (PBMCs)HIV-1_(NL43) Selectivity Compound EC₅₀ (μM) CC₅₀ (μM) (CC₅₀/EC₅₀)ODE-(S)-MPMPA 0.005 >10 >2000 HDP-(S)-MPMPA 0.10 >10 >100 HDP-(S)-MPMPG0.17 >100 >590

Example 63—Cytotoxicity Studies

Table 9 following provides comparative cytotoxicity data forODE-(S)-HPMPA and ODE-(S)-MPMPA using previously reported methods. Inliver cells (Huh 7.5), fibroblasts (HFF) and lymphoblasts (MT-2),ODE-(S)-MPMPA was remarkably less cytotoxic than the correspondingODE-(S)-HPMPA compound.

TABLE 9 Reduced Cytotoxicty of ODE-(S)-MPMPA versus ODE-(S)-HPMPA inVarious Cell Lines CC₅₀ (μM) ODE-(S)- ODE-(S)-MPMPA Cell type HPMPA (μM)fold change Huh 7.5^(a) 35.6 >150 >4.2 HFF^(b) 0.58 ± 0.3  23.8 ± 2.6 41MT-2^(c) 0.03 ± 0.02 22.0 ± 5.0 733 ^(a,b,c)Descriptions of cytotoxicitymethods: Huh 7.5 cells (Brown, N. A., Expert Opin. Investig. Drugs 18:709-725 (2009)); HFF cells (U.S. Pat. No. 7,044,772); MT-2 cells (U.S.Pat. No. 7,452,898).

As is generally known, ODE-(S)-HPMPA is highly active against doublestranded DNA viruses such as vaccinia, cowpox, human cytomegalovirus andherpes simplex virus (1) as summarized in Table 7. Surprisingly,ODE-(S)-MPMPA shows a dramatic loss of antiviral activity against doublestranded-DNA viruses representing several orders of magnitude whencompared with ODE-(S)-HPMPA.

Example 64—Inhibition of HIV Reverse Transcriptase by (S)-MPMPADiphosphate Chemicals

(S)-MPMPA diphosphate was prepared as described in Example 56.Radiolabeled [γ-³²P]ATP and cordycepin triphosphate ([α-³²P]3′-deoxyATP)was purchased from PerkinElmer, and unlabeled deoxynucleosidetriphosphates (dNTPs) were from Fermentas. RNA oligonucleotides werepurchased from Sigma.

Assays:

Oligonucleotide primer-template pairs were used as substrates forreverse transcriptase assays. Reverse transcriptase assays utilized RNAoligonucleotide templates. The primers were first end-labeled by using[γ-³²P]ATP and T4 polynucleotide kinase prior to annealing to thetemplate strand. Various combinations of dNTPs and (S)-MPMPApp wereadded. HIV-1 reverse transcriptase (from the NIH AIDS Research andReference Reagent Program) was used at a final concentration of 50 nM ina solution containing 50 mM Tris*HCl, pH 7.8; 50 mM NaCl; and 6 mMMgCl₂. After incubation of controls and (S)-MPMPA at 37° C. for 5 min,reaction mixtures were stopped by the addition of gel loading buffer[80% (v/v) formamide, 10 mM EDTA (pH 8.0), 1 mg/ml xylene cyanol FF, 1mg/ml bromophenol blue]. Reaction products were resolved on 10%polyacrylamide gels and analyzed by phosphorimager analysis aspreviously described (Magee et al., 2005) using a Typhoon 9400phosphorimager.).

Result:

(S)-MPMPA diphosphate inhibited HIV reverse transcriptase activity bychain termination.

Reference:

-   Magee, W. C. et al., Antimicrob. Agents Chemother. 49: 3153-3162    (2005).

VII. References

References cited herein are incorporated in their entireties and for allpurposes. Thus, the following documents are herein incorporated byreference in their entirety and for all purposes:

-   1. Rosenberg, I. et al., Coll. Czech. Chem. Comm. 53:2753-2777    (1988).-   2. Tokota, T. et al, Antiviral Chem. Chemotherap. 5:57-63 (1999).-   3. Kern, E. R. et al., Antimicrob Agents Chemother. 46:991-995    (2002).-   4. Beadle, J. R. et al., Antimicrob. Agents Chemother. 46:2381-2386    (2002).-   5. Beadle, J. R. et al., J. Med. Chem. 49:2010-2015 (2006).-   6. Hostetler, K. Y., Beadle, J. R. and Kini, G. D., U.S. Pat. No.    6,716,825, “Phosphonate Compounds,” Apr. 6, 2004.-   7. Hostetler, K. Y., Beadle, J. R. and Kini, G. D., U.S. Pat. No.    7,034,014, “Phosphonate Compounds,” Apr. 25, 2006.-   8. Hostetler, K. Y., Beadle, J. R. and Kini, G. D., U.S. Pat. No.    7,044,772, “Phosphonate Compounds,” Aug. 22, 2006.-   9. Hostetler, K. Y., Beadle, J. R. and Kini, G. D., U.S. Pat. No.    7,098,197, “Phosphonate Compounds,” Aug. 29, 2006.-   10. Hostetler, K. Y., Beadle, J. R. and Kini, G. D., U.S. Pat. No.    7,452,898, “Phosphonate Compounds,” Nov. 18, 2008.-   11. Brown, N. A., Expert Opin. Investig. Drugs 18:709-725 (2009)-   12. De Clercq, E., Biochem. Pharmacol. 73:911-922 (2007)-   13. Holy, A., Antiviral Res. 71:248-253 (2006)-   14. Koh, Y., et al J. Med. Chem. 48:2867 (2005)-   15. Mackman, Synthesis and antiviral activity of 4′-modified    carbocyclic nucleoside phosphonates (CNPs). Collection Symposium    Series 10:191 (2008)-   16. Prichard, M. N. et al., Antimicrob. Agents Chemother.    52:4326-4330 (2008)-   17. Sheng, X. C. et al., Bioorg. Med. Chem. Lett. 19:3453-3457    (2009)-   18. Valiaeva, N. et al., Antiviral Res. 72:10-19 (2006)-   19. Wyles, D. L. et al., Antimicrob. Agents Chemother. 53:2660-2662    (2009)-   20. Hostetler, K. Y. et al., Antimicrob. Agents Chemother.,    50:2857-2859 (2006)-   21. Magee, W. C. et al., Antimicrob. Agents Chemother. 49: 3153-3162    (2005).-   22. Hostetler, K. Y., Beadle, J. R. and Kini, G. D., U.S. Pat. No.    7,687,480, “Phosphonate Compounds,” Mar. 30, 2010.

What is claimed is:
 1. A compound having the structure of Formula (I):

wherein B^(N) is a substituted or unsubstituted nucleobase; L¹ is a bondor —O—; R¹ is halogen, —CF₃, substituted or unsubstituted alkyl,substituted or unsubstituted cycloalkyl, or substituted or unsubstitutedaryl; provided that, if L¹ is a bond, then R¹ is halogen, and if L¹ is—O—, then R¹ is —CF₃, substituted or unsubstituted alkyl, substituted orunsubstituted cycloalkyl, or substituted or unsubstituted aryl; and R²is a permeability enhancing moiety, a phosphate, or a diphosphate; orpharmaceutically accepted salt or solvate thereof.
 2. The compound ofclaim 1, wherein B^(N) is unsubstituted adenine, substituted adenine,unsubstituted thymine, substituted thymine, unsubstituted guanine,substituted guanine, unsubstituted cytosine, substituted cytosine,unsubstituted uracil, substituted uracil, 2,6-diaminopurine,6-methoxypurine, or 6-O-methylguanine.
 3. The compound of claim 1, withstructure of Formula (Ia):

wherein L¹ is —O—, and R¹ is —CF₃, substituted or unsubstituted alkyl,substituted or unsubstituted cycloalkyl, or substituted or unsubstitutedaryl.
 4. The compound of claim 1, wherein R¹ is unsubstituted alkyl,unsubstituted cycloalkyl, or unsubstituted aryl.
 5. The compound ofclaim 1, wherein R¹ is unsubstituted C₁-C₁₀ alkyl.
 6. The compound ofclaim 5, wherein R¹ is methyl, ethyl or isopropyl.
 7. The compound ofclaim 1, wherein R¹ is unsubstituted cycloalkyl.
 8. The compound ofclaim 1, wherein R¹ is unsubstituted aryl.
 9. The compound of claim 8,wherein R¹ is phenyl.
 10. The compound of claim 1, wherein R¹ issubstituted alkyl, substituted cycloalkyl, or substituted aryl.
 11. Thecompound of claim 1, with structure of Formula (Ib):

wherein L¹ is a bond, and R¹ is halogen.
 12. The compound of claim 11,wherein R¹ is fluoro.
 13. The compound of claim 1, wherein R² has thestructure of Formula (II):-L²-O—R³  (II) wherein L² is a substituted or unsubstituted alkylene,substituted or unsubstituted cycloalkylene, or substituted orunsubstituted arylene; and R³ is substituted or unsubstituted alkyl,substituted or unsubstituted cycloalkyl, or substituted or unsubstitutedaryl.
 14. The compound of claim 13, with the structure of Formulae(Ia1S) to (Ia7S):


15. The compound of claim 1, wherein R² is octadecyloxyethyl,hexadecyloxyethyl, hexadecyloxypropyl, 15-methyl-hexadecyloxypropyl,15-methyl-hexadecyloxyethyl, 13-methyl-tetradecyloxypropyl,13-methyl-tetradecyloxyethyl, 14-cyclopropyl-tetradecyloxypropyl,14-cyclopropyl-tetradecyloxyethyl, or1-O-octadecyl-2-O-benzyl-sn-glyceryl.
 16. The compound of claim 1 withstructure:


17. A pharmaceutical composition comprising a compound of claim 1 and apharmaceutically acceptable excipient.
 18. A method of inhibiting aviral reverse transcriptase comprising contacting a cell comprising aviral reverse transcriptase with an effective amount of a compound ofclaim 1, thereby inhibiting said viral reverse transcriptase.
 19. Themethod according to claim 18, wherein said viral reverse transcriptaseis from hepatitis C virus or a human retrovirus.
 20. The methodaccording to claim 19 wherein said human retrovirus is HIV.